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\V. K. No. 443. Issued Dec. 31. WIO. 

U. S. DEPARTMENT OF AGRICULTURE, 

If 5 WEATHER BUREAU. 
BULLETIN T. 



FROST AND TEMPERATURE CONDITIONS 

IN THE CRANBERRY MARSHES 

OF WISCONSIN. 



Prepared uiidtM- tlic ilirection iif WILLIS L. MOORE, Chief of Weather Bureau, 

I By 

HENRY J. COX, Professor of Meteorolosn-. 
II 




WASHINGTON: 

GOVKKNMEXT FKINTING OFFICE. 
1910. 



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JAN 20 191! 



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Page. 

ArKXOWLEDGMENTS '^ 

InTHODIX'TIOX " 

Cultivation of cranberries conlined to three States ~ 

(Occurrence of low temperatures and frost in moorlands 7 

Cultivating, draining, and sanding S 

Enemies to the cranberry croji - 

Comparison of temperatures in Massachusetts, Xew Jersey, anil Wisconsin H) 

Flooding to ward off frost 11 

Previous knowledge of low temperatures in the Wisconsin bogs 12 

Beginning of the investigation lo 

Characteristics of stations at Cranmoor, Berlin, and blather 17 

Equipment of the Mather station 18 

Equipment of the Berlin station 24 

Discrssiox OF the proiilem - 26 

.Minimum temperatures in shelters an<l in the open, both at 5 inches alio\ e the surface 2fi 

Readings of ex|)0sed minimum thermometers at the surface and at the 'i-inch height 35 

Observations of temperatures in soil and at the surface in different locations, Mather, Wis., 190i> ami liiOT. 37 

.Vii- temperatures and soil temperatures at Station 7 and Station 7a, Mather, Wis., September, 19i)6 43 

ilinimum temperatures at the coldest and at the warmest points on tlie bog, Mather, Wis Hi 

Comparison of mininuim temperatures at Station 1, in shelter, and on bog at Stations 3 and n, Mather, Wis. . b2 

Curves of air and soil temperatures at Stations 1 , H, and .5, blather. Wis., 1907 Mi 

Minimum temperatures at the coldest and at the' warmest points on the bog at Berlin, Wis ri8 

Minimum temperatures over dry and moist sand, Stations 3 and 4, Berlin, Wis til 

Minimum temperatures over peat bogs, heavily vined and thinly vined, Berlin. Wis., September, 190ti.. 62 
.Minimum temperatures over peat bogs and sanded bogs, thermometers exposed at ri inche- nbove the 

surface, at Cranmoor, Mather, and Berlin 63 

Readings of exposed mininiums at various elevations over bog and upland. Stations 2 and 9, Mather, Wis. . 6.5 

Comparison of wind movement over upland and marsh, and effect on temperature, Mather, Wis., 1907 7.S 

Exposed minimum thermometers over peat and sanded bogs at the surface, and at elevations of 5 inches 

and .36 inches, Berlin, Wis 76 

Maximum and minimum temperatures at different elevations, Station 9, Mather, Wis 78 

.\verage minimum temperatures for the season of 1907 for all locations, together with soil temperatures, 

Mather, Wis 78 

Relation between dew-point and minimum temperature 84 

Dew-point readings at Berlin 88 

Fog o\'er marshes, and low teiniieratures 88 

Special observations on critical nights at the Berlin marsh, September, 19iHi 89 

Effect of frost on the cranberry 91 

Disadvantage from reflowing 92 

Special data in connection with forecasting frost in the cranberry marshes 92 

Discussion of daily weather maps anil local conditions in connection with frosts in tin- Wisconsin bogs 

in 1906 92 

Discussion of daily weather maps and local conditions in connection with frosts in the Wisconsin bogs 

in 1907 95 

Conjparison between temperatures in the bog at Mather, Wis., and at United States Weather-Bureau 

ofHce, La Crosse, Wis 110 

Temperature conditions in the bogs during the seasons of 1908 and 1909... 114 

Temperature of the water in the reservoir 114 

CONCLISIOX 116 

.Advantages gained from sanding, draining, and cultivating 116 

.\ study of the general and local coinlitions necessary for frost in the marshes 117 

(3) 



ILLUSTRATIOT^S. 



Page. 

Fi<i. 1. State of Wisconsin. Map showing principiil counties in wliicli cranberries are grown 8 

2. Appleton marsh, Mather, Wis., showing north section of bog, also brush where lower reservoir is 

located. View from upland 12 

3. Diagram of the Appleton cranberry marsh, showing location of cultivated sections, the uplands, instru- 

ment stations, reservoirs, etc., Mather, Wis 13 

4. Daily weather map, 8 a. m., August 7, 1904 14 

5. Daily weather map, 8 a. m., August 8, 1904 15 

6. Fitch cranberry marsh, Berlin, Wis., looking north along county line ditch where Stations 2, 3, and 4 

are located !•> 

7. Station 1, Mather, Wis. Instrument shelter on upland near dwelling-. Photograph made in 190(5... 18 

8. Station 2, Mather, Wis. In bog over sphagnum moss and long grass outside cranlierry marsh- 19 

9. Station 3, Mather, Wis. Newly sanded, thinbj' vined 19 

10. Station 4, Mather, Wis. Newly sanded, heavily vined 20 

11. Station 5, Mather, Wis. In uncultivated bog 21 

12. Station 6, Mather, Wis. Old sanded, heavily vined - - 21 

13. Stations 7 and 7a, Mather, Wis. In .scalped section and on moss adjoining 22 

14. Station 8, reservoir, showing wide ditch and floating bog, Appleton marsh, Mather, Wis 23 

15. Station 9, Mather, Wis. In garden on upland 23 

16. Station 10, warehouse, Appleton marsh, Mather, Wis. Anemometer on cupola. Sunshine recorder 

on comb of building 24 

17. Fitch marsh, Berlin, Wis., showing car track on bog, dwellings, warehouses, and shanties 25 

18. Station 5, Fitch marsh, Berlin, Wis. In ferns and canebrakes 25 

19. Temperature curves for Stations 3 and 4, Mather, Wis., September 23 to 30, 1906 40 

20. First figure, traces showing average hourly soil temperature for the season of 1907 at a depth of 3 

inches and 6 inches, Station 3, Mather, Wis -iO 

Second figure, traces showing average hourly soil temperature for the season of 1907 at depths of 3 

inches and 6 inches. Station 5, IMather, Wis - -10 

21. (iraph of maximum and exposed minimum air temperatures and soil temperatures in bog, Mather, 

Wis., 1907 57 

22. Graph of maximum daily soil temperatures in bog, Mather, Wis., 1907 58 

23. Thermograph and anemometer records on July 27, 1906, Mather, Wis 7.t 

24. Thermograph record on the marsh, Berlin, Wis., noon. August 30, to noon, September 1, 1906, show- 

ing effect of passing clouds on temperature '^5 

25. Traces of thermograph in shelter <in upland and in vines on marsh. Uncorrected readings. Berlin, 

Wis., noon, September 4, to noon, September 5, 1906 , 76 

26. Temperature curves of air, soil, and water, Mather, Wis. , September 23 to 30, 1906 84 

27. Temperature curves of soil at Stations 3 and 5; also of air and water, Mather, Wis., September 16 to 

23, 1 906 84 

28. Temperature curves in shelter and in open in "theferns." Uncorrected readings. Berlin, Wis., noon, 

September 29, to noon, October 1 , 1906 91 

29. Traces of thermographs in shelter, both at Mather and Berlin, Wis. , from noon, September 23, to 

noon, September 24, 1906 - 94 

30. Thermograph traces in open over bog, from noon, June 5, to noon, June 6, 1907, showing effect 

of flowing of marsh on temperature of air at stations 3 and 5, Mather, \\Us 1 16 

31. Temperature curves in the vines on the marsh, Berlin, Wis., from noon, September 13, to noon, 

September 14, 1906, and from noon, September 27, to noon, September 2S, 1906 120 

(4) 



ACKNOWLEDGMENTS. 



The assistance of those who have taken part in this investigation is hereby acknowledged: 
Mr. R. N. Covert, United States Weather Bureau, performed work in the field at Mather in 
1906 and prepared several of the drawings used in the publication; both ^Ir. G. M. Richards 
and Mr. E. II Haines, United States Weather Bureau, carried on the field work at Mather 
during the season of 1907, and the latter also made the computations appearing in the tables. 
A vast amount of tabulated data has been prepared, although few of the tables have been 
published, as a whole, for want of space. 

Acknowledgment is also made of courtesies extended bj Mr. II. R. Laing, manager of the 
Stanley Marshes at Berlin, Wis.; Judge John Gaynor, Grand Rapitls, Wis.; Pi-of. A. R. Whitson, 
of the University of Wisconsin; Mr. J. N. King, Mather, Wis.; the Federal Cranberry Com- 
pany, South Carver, Mass.; and ilr. J. J. White, of New Lisbon, N. J. 

Prof. W. J. Humphreys, I'nited States Weather Bureau, has kindly read the manuscript 
and has offered valuable suggestions for which the writer is greatly indebted. 

(5) 



AN INVESTIGATION OF TE>\PERATLRE AND FROST CONDITIONS IN THE 
CRANBERR^ MARSHES OF WISCONSIN. 



IXTRODUCTIOX. 

CuUh-atioii of cranherries confned to tJiree States.— The cultivation of cranberries in the 
United States is confined mainly to three States— Massachusetts. New Jersey, and Wisconsin. 
In Massachusetts the oranherry-growing region in turn is hniited almost entirely to the counties 
of Ph-mouth. Barnstable, and Bristol: in New Jersey, to Cape May. Atlantic, Gloucester, Bur- 
lington. Ocean, antl Monmouth counties: and in Wisconsin, to Wood. Jackson, Juneau, and 
Momoe counties in the Wisconsin River Valley, and to Waushara and Winnebtigo counties in 
the Fox River Valley. (Fig. 1 for map of Wisconsin.) For several years there luxs betai a 
mai-sh in the village of Cameron, Wis., and recently one was started in the Lake Superior 
region near the town of Ashland, Wis. The cultivation is slowly extemling to Michigan and 
Minnesota, and even Oregon, but the cultivated marshes in the three states last named are 
at present comparatively of no importance. There are, of coui-se. wild cranberry mai-shes in 
several of the Northern States, but the berries pickeil theivfrom are seldom sufficient to supply 
even local needs. They are of little consequence a^ compareil with the fruit produced in the 
cultivated mai-shes of Massachusetts, New Jersey, and Wisconsin. 

The cultivation of cranberries a^ an industry is by far older ami more siict-essfid on Cape 
Cod than elsewhere. Nearly every bog. whether large or small, on the Cape, has been con- 
verted into a cranberry mai-sh, and there we find the highest state of cultivation, the bogs being 
almost invariably sanded, well drained, and free from weeds. The Massachusetts bogs are 
individually small as compared with those found on the extensive moorlands oi New Jersev 
and Wisconsin: and often one cranberry marsh in ila^sachusetts is made up of several small 
sections. That of the Federal Cranberry Company, near South Carver, Mass., which annuallv 
produces about 10.000 to 14.000 barrels of berries from a total area of ISO aci-es. is composed 
of IS little bogs, separated naturally by hard land, but connected, nevertheless, artificiallv by 
ditches for the purpose of flooding: while, on the other hand, the Wisconsin moorlands ai'e 
extensive and often stretch for many miles. The Wisconsin River Vallev. the chief cranbeirv- 
growing section of the State, comprises an area of about SOO square miles. o50 of which are 
mai-sh land, the remaining portion being •' islands ' or hard land. In topography, the moor- 
land sections of Xew Jersey more nearly resemble those of Wisconsin than they do those of 
Massachusetts. The average :Massaoluisetts crop is about 300,000 barrels, while New Jersey 
and Wisconsin contribute 150,000 and 7.5,000 barrels, respectively. 

Occurrence of low temperatures and frost in moorlaruis. — During clear cool nights the air 
usually is much colder over bottom lands, where the cranberry grows, than on neighboring 
slopes and uplands. This is especially true when but little wind or a calm prevails. During 
such nights the ground loses its heat rapidly by ratliation, and the air lying immediately above 
is cooled. When cold heavy air lies over uplands ami slopes it gradually settles through gravity 
to lower levels, being replaced by warmer air brought from above, which is in turn cooled. In 
fact, a gradual descending flow is established from the uplamls to the valley, so that the cold 
air of the hilltops is di-ained away. Quite frequently crops in bottom lands suffer severely 
from frost, while on neighboring uplands the temperatures are not injurious. It is well known 
that the tobacco fields on the slopes of the Connecticut River often escape injurv when damag- 
mg frosts occur lower down. The cranberry, moreover, has its habitat only in the bottom 

(7) 



8 

lands where frost is most likely, but protection may be afforded by covering the bbg witii 
water stored in adjacent reservoirs. 

Cultivating, draining, and sanding. — Protection to a considerable extent may also be 
obtained by cultivating, draining, and sanding the cranberry marsh. In bottom lands the 
vegetation is generally dense and the soil damp. Leaves and grasses are excellent radiators, 



STATE OF WISCONSIN. 



Scale of Miles. 

to 20 JO 40 so so 70 




Milvf'aiikee 



MAP 



SHOWING PRINCIPAL COUNTIES 
CRANBERRIES ARE 6R0WN. 



IN WHICH 



G.fl.%9/,o 



Fig. 1. — Map showing principal counties in which cranberries are grown. 

and consequently lose their heat rapidly. The heat lost by radiation passes thi'ough the air, 
and does not warm it if the air is dry; but when the air is moist some of the heat is absorbed. 
Moreover, where the vegetation is dense, the soil beneath is screened from insolation, so that it 
is heated but little by the sun during the day, and has but a small supply of heat stored up. 
As a consequence the temperature of air Iving over a field with a dense growth of vegetation is 



relatively low during any cold clear night. Cultivation, by reducing the amount of vegetation, 
permits greater heating of the soil during the daytime, and consequently there is a larger store 
of heat to give out at night. 

The peat soil found in bottom lands, on account of its capillarity, brings water to the 
surface, and the cold produced by the evaporation of this moisture is considerable. This is 
especially the case where the drainage is poor. Ditches, run at frequent intervals in the marsh, 
serve to drain the water from the surface and to reduce the amount of evaporation; and, at the 
same time, to conduct water of comparatively high temperature from adjacent reservoirs to 
the bog Avhen frost threatens. 

The moisture at the immediate surface may also be reduced by sanding — placing a layer 
of sand on the surface of the peat — because sand, almost wholly lacking in capillarity when 
coarse, does not bring the water to the surface. Moreover, sand on account of its low specific 
heat is warmed more easily, and acts as a conserver of heat. A sanded surface absorbs solar 
radiation tolerably well, and gives out heat by radiation only slowly. It cools largely by con- 
duction to the atmosphere, thus serving to modify night temperatures by heating the air Ij'ing 
above. 

Very few of the Wisconsin bogs have been sanded, and many have a rank growth of vege- 
tation, grasses and ferns often attaining a height of 2 feet or more. Frequently canebrakes 
and sagebrush are found. The uprights from the cranberry vines are usually more than 6 
inches in height, and occasionally 12 inches or more. The growth of the vines is very rank, 
and the marshes are seldom kept clean, so that even when the vines are laden with berries, one's 
attention is attracted to the vegetation rather than to the fruit. On the other hand, the Cape 
Cod marshes are invariably sanded and the vines are thin, the uprights seldom reaching a height 
of more than 5 inches, as the coarse sand employed dwarfs the vines. The berries, moreover, are 
usually so plentiful that one hardly notices the vines. The contrast between the Massachusetts 
marshes and those of Wisconsin is so pronounced that the growers in Wisconsin have been said 
to raise vines, and those on Cape Cod berries. This statement has some foundation in that the 
yield per acre on the Cape is about double that in Wisconsin. The marslies in Xew Jersey 
perhaps take middle ground between those in Massachusetts and Wisconsin. They are usually 
well cultivated, but only infrequently sanded. In fact, not 15 per cent of the New Jersey bogs 
are sanded. The growers there prefer to confine the cranberry culture to the natural peat soil, 
believing that it produces a crop of better quality than does a sanded bog, and that the expense 
of sanding is not justified by the increased returns. The right kind of sand is near at hand for 
the Cape Cod growers, but it is not easily available for many of the growers in New Jersey and 
Wisconsin. A coarse sand, resembling gravel, is ordinarily used, fine sand packing too hard 
and being therefore valueless. 

The drainage in the bogs of Cape Cod, moreover, is excellent, the marshes during the 
growing season usually being as dry as an ordinary prairie — in strong contrast to the dampness 
of the Wisconsin bogs. The little need for refiowing on the Cape permits the growers there to 
keep the ditches dry during the sununer season, but the Wisconsin growers are obliged at all 
times to keep a certain amount of water in the ditches in order to facilitate refiowing when 
frost is expected. The Wisconsin marshes are consequently more or less damp during the 
entire season. Cultivation, moreover, is practiced on Cape Cod, preventing the rank growth of 
vegetation and weeds that screen the soil from the sun's rays. Cultivating, draining^ and 
sanding thus serve to cause higher soil temperatures in the daytime, and, as a result, relatively 
higher air temperatures at night. 

These facts — the advantages gained from cultivating, draining, and sanding — were quite 
apparent to the WTiter after a preliminary investigation; ami an effort will be made in this 
report to show in detail, by figures, the relation between the air temperature and the character 
of the soil and vegetation lying beneath. 

Enemies to the cranberry cro^j.— The great enemies to the cranberry are frosts, floods, 
droughts, worms, and fire; and whOe the damage from frost is seldom very great in ilassa- 
chusetts and New Jersey, frost is the berry's greatest enemy in Wisconsin. The meteorologist is 



10 

chiefly interested in the frost problem, as far as cranberry growing is concerned. However, 
floods and freshets during the gro^nng season frequently work havoc with the cranberry crop, 
and it was because of the floods in the s])ring of 190.S that the crop in the vicinity of Berlin, 
Wis., was nearly a complete failure. In that year it was not possible to coiupletely draw ofl' the 
winter flow until the last of June, instead of in May as usual, and consequently the crop of ber- 
ries in some bogs was confined to the tops of the vines while in others the crop was a total failure. 
Such surplus of water not only destroys the crop of the current year, but also weakens the 
vines so that they show the injurious effects for several years afterwards. The freshets of the 
spring and summer of the year 1906 were responsible for great damage to the New Jersey crop. 
If a flood covers the marsh during extremely warm weather there is damage to the vines and 
berries from scalding, the reflection of the heat from the surface of the water cooking the berries 
until they resemble baked apples. This liability to damage is ahvays considered by the growers 
in reflowing their marshes in oi'der to drown the vine and fruit worms, and it is necessar}" to 
select a period of cool and cloudy weather, if possible, so as to get the best results with the least 
injury. Damage is also liable frf)m lack of water, not only in the insufficient supply available 
for reflowing the marsh for frost protection or otherwise, as in Wisconsin in 1909, but because 
in seasons of great drought the vines become parched and extensive fires are likely to occur. As 
a result of the drought of 1894, 95 per cent of the vines in the Wisconsin Eiver valley were de- 
stroyed by fire, but the marshes have since been replanted. In 1909, 60 to 75 per cent of the 
Wisconsin crop was lost in the severe frosts of September because of lack of \\'ater for reflowing. 
Comparison of temperatures in Massachusetts, New Jersey, and Wisconsin. — From a study 
of the temperature conditions in the three states during the growing season it is evident that 
the temperature is usually much lower in Wisconsin than in the eastern cranberry-growing 
sections. From a comparison made between temperature readings observed in shelters on 
hard land at Plymouth, Mass., Whitebog, X. J., and Mather, Wis., in the midst of the respective 
cranberry districts, for the months of May and September, 1 906 — critical months in the cranberry 
industry and fairly typical ones — it was found that the minimum temperature at Plymouth 
averaged higher by 5.1° in May and 4.5° in September than at Mather; while at Whitebog, for 
the same months, the minimum temperature averaged S.l° and 7.6°, respectively, higher than 
at Mather. The average readings at the respective stations were as follows: 



Mather. \\ is 

Plymouth, Mass 
AVhitebog, N. J. 



May. 


September. 


o 

41.9 
47.0 

oO.O 

1 


50.5 
53.0 
68.1 



The difl'erences between these averages represent approximately the relation between the 
minimiuii temperature readings in the bogs in the various States, although for ]nirposes of 
comparison it was found necessary to use readings made on hard land. The first frost in the 
Xew Jersey bogs in autumn usually occurs from two to three weeks later than in W^isconsin. 
In 1906, for instance, the first light frost at Whitebog occuiTed on October 8, and a heavy frost 
was not rei)orted until October 11, while in Wisconsin the first frost was noted September 14" 
and the first killing frost on September 27. 

Frost is so damaging in the Wisconsin bogs that means of protection from it must be the 
first provision made by the cranberry grower. Damaging frosts invariably occur there in the 
month of May, often in June, rarely in July, occasionally in August, and invariably again in tiie 
month of September; while midsummer frosts are miknowu in the East and seldom occur in the 
month of June. In the East severe frosts do not occur so late in the spring or so <^arly in the 
autumn; and consequently the seasons in Cape Cod and Xew Jersey are much longer than in 
Wisconsin. The season in the latter state is quite short, and it is only during a year in which 



"About two weeks later than the average. 



11 

till' crop season has a temperature far al>ove the normal that the cranberry grower in Wisconsin, 
w itliout means of protection from frost, can hope to gather even a fair crop. 

Flooding to ward off frost. — It is apparent from the foregoing that, although the Wisconsin 
crop is usually smaller than that of either Massachusetts or New Jersey, it has special need of 
proj)er protection from frost, and hence the need of accurate frost warnings. The large majority 
of the Wisconsin and New Jersey marshes and a limited number of those in Cape Cod are connected 
with vast reservoirs, which are used for flowing the bogs in winter in order to prevent wmter 
killing, and for reflowing tluring tlie growing and jiicking season for the purpose of warding ofl' 
frost. In fact, as stated above, the first thought of the Wisconsin grower is to provide ample 
water supply. Some of the bogs in Massachusetts have no watersupply, even for winter flowing, 
but all the bogs in Wisconsin and nearlj' all those in New Jersev have ample supply for this pur- 
pose. Growers usually tiu-n on the winter flow in November and keep it on throughout the entire 
winter. Some Wisconsin growers take the winter flow oft' again about April 15, but the majority 
retain it until after the first of May, and a few mitil the last of May. Those who keep the flow 
on until late in May do so believing that the water prevents the hatching for that season of the 
fruit worms with which the marshes have been afflicted. Some growers who take the winter 
flow off the marsh early reflow during Jime and keep the water on for a few days, if a ]:)eriod of 
cool weather prevails, in order to guard against the fi-uit worm. It is supposed that the eggs 
are laid in May along the dams, and that if, thi'ough drowning, they are prevented from hatching 
during the month of June, the worms will not apj)ear that season. As a period of three months is 
sufficient to mature the crop, should the water be retained until June 1, the cranberries would 
ordinarily be ripe for picking about September ] . Frecjuent reflowing, however, if the fruit 
is set, injures the vines and the berries as well. Moreover, in flowing and reflowing, damage 
is sometimes done to the crop by lime or otlier impiu'ities in the water. 

Most of the Wisconsin marshes can be reflowed in about four hours, but there are a few in 
that state that can not be satisfactorily flooded in anticipation of frost. In the marshes of 
the East, of course, as stated above, frosts are not as serious as in Wisconsin because of their 
more favorable geographical location. On Cape Cod, moreover, where intensive farming is 
practiced in the shape of santling, draining, and weeding, there is not the same need for reflowing 
to ward off frost. Onlv about 30 per cent of the Cape Cod bogs can be reflowed as a means of 
warding off frost, and this can not be done twice in one week in more than 10 per cent of these 
bogs during a season of normal rainfall. In New Jersey somewhat better conditions as regards 
water supply prevail. Many of the bogs, as the excellent one at \Miitebog, for instance, usuallv 
have ample water supply. With such limited water protection in Wisconsin as is usuallv 
available in Massachusetts bogs, success in the industry woiddbe quite impossible. In reflowing 
a marsh the amount of water used depends upon the severit}' of tlie frost expected ; sometimes 
it is sufficient merely to raise the water in the tlitches ; at otlier times to bring it up to the surface 
of the marsh ; and, in extreme cases, to completely cover the vines and berries. 

The Appleton marsh at Mather is a typical Wisconsin bog, and is usually provided with 
ample water supply. (Figs. 2, 3.) The reservoirs, both upper and lower, are largely floating 
bogs. Wide ditches connect the reservoirs with the cultivated sections and smaUer ditches 
run through the sections from 80 to 100 feet apart. Water is usually present in the ditches to 
a depth of 1 to 2 feet, the surface of the water averaging perhaps about 12 inches below the 
surface of the marsh itself. These ditches are provided with gates to regulate the flow from 
the reservoirs. There is also a gate at the foot of the marsh (marked "B" on Fig. 3), which 
is shut during flooding and opened later in order to drain the water oft". "Wliile 3 acres of reservoir 
AIT. generally sufficient for flooding 1 acre of vines, yet the acreage of the marshes of Wisconsin 
usually has about one-tenth planted in vines, ami the rest is given over to reservoirs and protec- 
tion of water rights. 



12 



Previous knowledge of low temperatures in the Wisconsin bogs. — It has been known»f()i- many 
years that the minimum temperature in the Wisconsin bogs on clear cool nights falls far ])elo\v 
the readings of tlie instruments at the nearest Weather Bureau station, and that frost often 
occurs in these bogs when there is no evidence of it on hard land. Prof. Willis L. Moore, now 
Chief of the United States Weather Bureau, was the first forecaster to give this subject special 
attention. It was in 1S9.3, wliilo in charge of the Milwaukee office, that lie visited several of 
the bogs in the Wisconsin River valley. Later, other officials from time to time have visited 
these marshes. Professor Whitson, of the Wisconsin Experiment Station, undertook an investi- 
gation in 1904 in connection witli the Branch Experiment Station located at Cranmoor. As 
a preliminary to the investigation started by the United States Weather Bureau, efforts were 
made to secure reliable data from various Wisconsin growers relative to the occurrence of frost 
and freezing temperatures diu'ing pn^vious years, but it was fomid that ver\' few of them had 
kept a record of any value. Som'^ data, however, have been furnished by Mr. C. H. Johnson, 
manager of tlie Wyatt and Purdy marsh at Valley Junction. His statement shows tliat during 




Flf.,. *.;. --A|-iiK.'liin mar-li. MuIIkt. Wi--.. siiuwiuL,' ii..nh ,...;,,-;: >;; :>m.,. .iI.m; hi;i-:: where 
lower reservoir is local ud. View from uplnnd. Directly beyond the brush i^ loc;ilfd the 
main section. Shelters at Stations 3 and 4 appear an the extreme left. 

the period of twenty years from 1SS5 to 1904, inclusive, frost usually occurred in the summer tit 
Valley Jimction before the end of August. In 1885 heavy frost was recorded on August 22, in 
1S90 light frost occurred as early as August 10, and heavy frost in the same year on August 23. 
In several years of this period frost occurred more than once during the month of August, but 
Mr. Johnson has no record of its occiu'ring in July; however, in a few instances, frost has been 
observed in that month by other growers. 

The frost which occurred on June 11, 1903, in Wisconsin, did much damage, and, as a 
result, less than half a crop was harvested in that year. Some of the growers lost nearh' all, 
although others, because of their location and better facilities for protection, secured nearly a 
full crop. The frost of August 8, 1904, reduced the crop of berries to aliout 60 per cent of that 
iisually secured. No damage resulted in marshes which had been flooded before the frost. 
Ihifortunately, some of the growers did not have their ditches clean, and the water in them was 
low, so that there was great delay m reflowing; and, as a consequence, considerable damage was 
done bv the frost, 



13 



DIAGRAM OF THE APPLETON CRANBERRY MARSH 

SHOWING LOCATION OF CULTIVATED SECTIONS, THE UPLANDS, INSTRUMENT 
STATIONS, RESERVOIRS, ETC. 

MATHER, WIS. 9 y -^ 



arrows show direction of flow 
of drainage 

contour lines are given for elevations 
above: the marsh at station 3. 

a a trees and brush 




ISLAND,; 



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hi^'^^-\i X, 






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^SLi^ Ay^A^^rt A AAA1 



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V^-* A^ A^'z-^v V V A ;»rr#^ A A ; aa ; 

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Fi(i. 3.— Diagram of the Appleton cranberry uiarsh, Mather, Wis. 



14 

TJiis freeze of August 8 is remembered as more severe than any previous one in n^simimer 
within the recollection of the Wisconsin cranberry growers. The ilay before, August 7, was 
cloudy, owin^ to a slight disturbance which was centered over Lake Michigan. The sun's 
rays were obstructed by dense clouds which kept the temperature of the air in the shade ilowu 
to a maximum of 65° to 70°. The clouds, however, cleared away just at sunset and the wind, 
which was fresh during the day. became light in the evening, and the barometer rose steadilv. 
Thermometers exposed in the vines in peat bogs at Mather and Cranmoor, Wis., recorded 
minimum readings of 29° and 26"^, respectively, on the morning of August 8, and frosts were 
severe generally throughout the moorlands. No fi-ost was reported that morning from any 
of the regular Weather Bureau stations, except Escanaba and Houghton. The minimum 
temperature at La Crosse, Wis., was 48°; Green Bay, Wis., 45°; Duluth, Minn., 50°; and 
St. Paul, Minn., 48° — all being readings from instruments located in shelters on the roofs of 




Fig 4.— Daily weather map. S a. m., August 7. 1904, 

buildings. It would seem as if only an ext raordinary condition could produce such low tempera- 
tures in midsummer. 

A special study shoidd be made of liio weather ma])s of August 7-8 (Figs. 4, 5), showing 
the general weather conditions prevailing throughout the entire country. On August 7 the 
slight disturbance, marked "low,'' was central over Lake Michigan, while an area of high 
barometer, inclosed by the isobar of 30.2 inches, covered the Dakotas. The temperatures in 
North Dakota were in the forties, and the lowest reading was 40° at Minnedosa, Manitoba. 
The "low" remained nearly stationary dm'ing the greater portion of the day, causing the cloudi- 
ness and the relatively low day temperatures in Wisconsin, above referred to. It advanced east- 
ward, however, by evening. On the morning of August 8 the high was directly over Wisconsin, 
with the center still inclosed b}^ the .30.2-incli isobar. 

As a general principle, it may ho stated that the most favoral)le conditions as regards thc^ 
production of low temperatures locally in the damp lowlands are an overcast sky during the 



15 



daytime, so that tlie soil is not heated by insolation; clearing at sunset, so that there may be 
active radiation at night; a rising anil a comparatively high barometer which permits a settling 
of the cold air toward the ground; a fresh wind in the daytime, which reduces the temperature 
of the surface of the soil by the cold of evaporation, and which dies down at sunset and conse- 
cjuently does not interfere with the gradual settling of the cold air to the ground ; and compara- 
tively low humidity, as radiation from the grounil through dry air is freer, or, in other words, 
the lower the humidity the less the absorption of heat by the air. On August 7-8, 1904, all 
the conditions were apparently present for the production of abnormally low minimtmi tempera- 
ture, viz: Cloudiness and fresh breeze during the day, followed by clearing in evening, rising 
barometer, falling of the wind, and comparatively low humidit}'. 

Beginning of the investigation. — As stated above, it was found that but few of the Wisconsin 
growers had kept any record of temperature and frost contlitions in the bogs. Visits were 




Fig. 5.— Daily iveather map, 8 a.m.. August 8, 1904. 

made to several of the marshes ami communication was had with many of the growers for the 
purpose of securing any available data in anticipation of the proposed investigation. These 
men are usually intelligent and keen, and intensely interested hi their work, and consecjuently 
it is strange that so little attention had been given to the preservation of temperature records, 
as definite knowledge of the subject of temperature in the bogs should be of permanent value. 
Moreover, there had been a wide divergence of opinion among the growers regarding the problem 
which was being undertaken, l)ut all seemed to be interested and willing to cooperate. The 
growers stated that occasionally frost attacked one section of a marsh and left the remainder 
untouched, without apparent cause; also, that damage was sometimes done to one marsh 
while another adjoining escaped injury. They were naturally puzzled over these unusual 
features. In the investigation which Prof. A. R. Wliitson'^ had started at the Cranmoor Experi- 
ment Station in 1904, the observations were restricted almost entirely to artificial conditions 

« Wisconsin Bulletin 119, A Report on Cranberry Investigation. 
519.;6°— Bull. T— 1) ■! 



16 

created for the purpose. The section at the Brancli Experiment Station phinted witli cran- 
berries is not representative of the Wisconsin cranl)erry marshes in actual operation, hut rather 
of the conditions prevailing on Cape Cod. The plat of tjround at Cranmoor is so small that the 
various thermometers used in TVIiitson's investigation were comparatively close together, and 
all were affected more or less by tiie same conditions. Whitson apparently lost sight of tiie 
fact that a thermometer exposed at any point is largely affected by its environment, as well 
as by the conditions at the immediate i>oint of exposure. While "WHiitson has endeavored to 
leail tlie way, anil to induce Wisconsin growers to adopt eastern methods of sanding, cultivating, 
and draining, the latter have been very slow to follow. For certain reasons that will develop 
later tlie majority of the AVisconsin growers have not considered it advisable to follow the 
Massachusetts method in sanding and cultivating. 

It was deemed best to conduct the investigation by the W^eather Bureau as far as practicable 
in typical bogs, fidly representing the various conditions existing. In beginning tliis work in June, 
1 906, special cranberry marsh stations were established at Cranmoor, blather, Berlin, and Cameron 
and continued tliroughout the season. The Cranmoor station was at the Wisconsin Branch 




Fig. 6.— Fitch cranberry marsh, Berlin. Wis., hjoking north along county line ditch where 
Stations 2. 3, and 4 are located. Fog in the distance on north side of the marsh just after 
daybreak. 

Experiment Station in charge of Professor 'Wliitson, referred to al)Ove. It is situated in the 
center of the Cranmoor region, and adjoins the well-known Gaynor-Blackstone marsh. Tht^ 
Appleton marsh at Mather was selected because it is typical of the Mather district. (Figs. 2, 
3.) Both Cranmoor and Mather are located in the extensive moorlands of the Wisconsin 
River vallev. The Berlin station, established at the Fitch marsh, is S miles northeast of the 
city of Berlin in the Fox River valley, and in a much less extensive moorland. (Fig. 6.) The 
Fitch marsh is old and fairly productive, but poorly drained and lacking in satisfactory means 
for reflowing. The Cameron station was situated in the northwestern part of tiie State, and 
the marsh at that point was selected on account of its geographical location and because it was 
in a narrow gully between stretches of hard land. At these four stations special local observers 
were secured. Wliile at Cranmoor, the observer was Mr. O. G. Malde, an assistant to Pro- 
fessor Whitson of the Experiment Station, at the remaining stations the persons employed 
were managers of the respective marshes. All of the local observers except the one at Cameron 
-had long experience in making observations. In July, 1906, moreover, an experienced observer 
was sent from the Ciiicago office to Mather to conduct observations in detail, and the writer 



17 

himself spent the greater portion of the season in personal work at Mather and Berlin in order 
to secure the data first-hand. 

An extensive equipment was secured for the Mather and the Berlin stations for the purpose 
of goinc; into the subject exliaustively. and thus fuidinci; the true reasons for the comparatively 
low temperatures in the bogs and their great variation. It was expected that the work in 1906 
would be merely preliminary and tliat no definite results could be secured in so brief a period; 
that only sufficient data could be obtained in the first season to prepare more definitely for the 
work of 1907. This j)roved to be true, as considerable experimenting was required to determine 
how and where the various instruments should be exposed. ^Moreover, the soil thermographs, 
ordered from abroad the previous winter for this special work, did not arrive in this countrv 
until almost the end of the season, and the results obtained from some of them for tlie month of 
September, while they were in operation, are of little value. It was extremely difficult to 
adjust them so as to secure accurate records. Furthermore, the observations made at Cameron 
were found to be unreliable, and they have not been used in this discussion. The result of the 
experience with the Cameron observer suggests that observations for scientific purposes should 
never be intrusted to an untrained observer, even though he receive compensation. The data 
must be accurate; otherwise the deductions and conclusions have little value. The observa- 
tions appearing in tliis bulletin, with the single exception of Table 12, were made by regular 
employees of the Cliicago Weather Bureau office. 

The stations at BerUn and Cameron were closed at tlie end of the season of 190(). In 1907 
the cooperation of the Cranmoor Experiment Station was continued and the work at Mather 
was much enlarged, trained observers from the Chicago office conducting the observations there 
from early in May until the end of October. Also during the seasons of 1908 and 1909 a limited 
number of observations were secured from Cranmoor and Mather. Moreover, observations 
made at these two stations, beginning with 1905, have been telegraphed daily to the forecast 
center at Cliicago for the use of the forecaster in i.ssuing frost warnings for the Wisconsin cran- 
berry marshes. The Berlin marsh liad no facilities for telegraphing and its report was not 
transmitted daily. 

Characteristics of stations at Cranmoor, Berlin, and Mather. — The three marshes selected for 
the investigation are wideh' separated and fairly representative of the conditions prevailing in 
Wisconsin marshes. Owing to the high state of cultivation at the Cranmoor Experiment Station 
there is usually no need for reflowing during the entire cranberry season in or<lcr to ward off 
frosts. Tliis is in strong contrast to the conditions prevailing in the Gaynor-Blackstone marsh, 
immediately adjoining, which represents the average concUtions found in the Wisconsin bogs. 
The Appleton marsh at Mather differs from the Gaynor marsh in tiiat the greater jiortion of it 
has been sanded. It was sanded in 1S9S to a depth of about 2 inches, and sanding was again 
done in the winter of 1905-6, but in the meantime a layer of peat an inch or two in thickness had 
accumulated over the former sanding. Having ample water supply, it can usually be reflowed 
in about four hours. This marsh was fairly dry during the season of 1906, but in 1907 it was, 
unfortunately, at frequent ])eriods very wet. This latter condition was due primarUv to heavy 
rains and to the breaking of the dams in the reservoir of a marsh immediately adjoining. The 
water "backed up" on the Appleton marsh at times, and it was drained off \dth difficulty; 
and consecpiently, the conditions as regards moisture were not as typical of that marsh in 1907 
as in 1906 and the exposure of the instruments, as a result, not as satisfactory. Some of the 
instruments exposed at the surface of the bogs were, at times, covered with water. The reflow- 
ing in anticipation of frost also affected the exposure of the instruments, but that was a com- 
plication that could not be avoided, and in these cases, the readings have either been estimated 
or tlu-own out entirely. 

The Fitch marsh at Berlin (Fig. 6). as stated already, could be reflowed only with great 
difficulty, and it was seldom attempted, the course usually taken in anticipation of frost being 
to raise the water high in tlie ditches. The marsh was naturally wetter than the Appleton 
marsh, tlie drainage not being as good. In the season of 1906, when observations were made 



18 

at Berlin, there was little change in the amount of moisture in the hog, except imn^diatclv 
following the heavy rain of July 29, when 4.99 inches fell in a few hours during a thunderstorm. 
As a result of this fall over the bog and the drainage from the surrounding country, the water 
was over a foot in depth on the marsh, and several da\-s were required to drain it oflF. 

The stations that were estal)lished at tlie Appleton marsh at Mather in 1906 were con- 
tinued during the season of 1907 without cJuuige as regards location, although the character of 
the equipment was improved considerably. (Fig. 3 shows plan of nnirsh, giving locations 
of cultivated sections, reservoirs, uplands, brush, woods, etc. The figures mark the stations 
and the letters mark the gates that control the water supply.) In comparing Figures 2 and 3 
it should be noted that in the photograph (Fig. 2) the marsh in the foreground, which is inter- 
sected liy numerous ditches for the purpose of flowing and reflowing, is itlentical witli the culti- 
vated sections in which Stations 3 and 4 are located, aj)pearing in Figure 3. The adjoining 
uplands or islands [any stretch of liard land in tiie bog region is called an island], have an ele- 
vation of 10 to 15 feet aljove the surface of the nnirsh. The peat and muck in this marsh is 




Fig. 7.— stiUinn 1, MiUher. Wis. 

Instrument .shelter on upland nfiLnlwellinf;. I'hiiii>s,'raiih made in 1906. Shelter lowered 
from an elevation of s feet to .5 feet in l'.>07. I-tain gages about 20 feet to tlu- right. They do 
not niipenr in the picture. Garden in the baeksfround where Station No. 9 was located. 

from 10 to 25 feet in depth, and the soil of the surrounding islands is a sandv loam, luostlv 
covered with grass, with brush and trees at intervals. 

Equipment of the Mather Station. — The instruments at Mather were located at stations 
widely separated and in the midst of large sections as far as possible typical of the conditions 
prevailing at the points where the instruments were exposed. An exception was made in fliis 
respect at Station 7. The following was the equioment in operation in 1907: 

Station 1, north of the dwelling house on Long Island. The shelter (shown in the ])hoto- 
graph. Fig. 7, taken in 1906) was lowered in 1907, so that the floor was al)0ut 5 feet above 
the ground, instead of 8 feet as in 1906. Equipment: Maximum, minimum, and exposed 
thermometers, also air thermograph, all in the shelter. Station 1 was also ]n-ovided with an 
Assman aspiration psychrometer, attached to the northeast corner of the dwelling, and two 
rain gages. A barograph was kept in the dwelling. 

Station 2 (Fig. S), in the bog over a dense growth of sphagnum mess, outside of the 
cranberry marsh proper. The moss probably reached to a depth of 6 feet, and, like a s])onge, 
was saturated with water. The station had. liowever, tlie advantage of being outside the 



19 




Fig. 8.— Station •_'. Matlier. Wis. 

In bcig over sphagnum moss and long grass outside cranberry marsh. Photograph made in 
I'JOe. Thermometers at various elevations up to 36 inehe.s attached to post.s in 1907. 




Fig. 9.— .Statinn 3. JIather. Wis. 
Newly sanded, thinly vined. Photograph made in 1907. Grasses seen in the photograph 
were not present in 1901'., and the vines were not so dense. 



20 

cultivated sections that were flooded in anticipation of frost, and consequently the c^jjditions 
as regards moisture varied less here than elsewhere in the hog. Equipment: Air thermograph 
and maximum and minimum thermometers in the shelter ahout 5 inches above the surface of 
the marsh. Outside and immediately to the north of the shelter were two posts on which 
were fastened fi maximum and 6 minimum thermometers facing south at the following eleva- 
tions: Surface, 21 inches, 5 inches, 7 J inches, 12 inches, and 36 inches; also minimum ther- 
mometers at additional elevations of 10 inches and 15 inches; 2 soil thermometers in the moss 
at deptlis of 3 inches and 6 inches, respectively; soil thermograpli, the ])ull) of wliich was 
exposed at a depth of 3 inches in the moss. 

Station 3 (Fig. 9), in the cultivated section was heavily sanded durmg the winter of 
1905-6. It was thinly vined during 190G, and relatively so as compared with tlie other stations 
in the cranberry marsh in 1907, but the vegetation was then more dense than in the jirevious 
year. It may be considered as representing the best conditions on the bog as regards sandmg, 
cultivating, and draining. Equipment: Minimum thermometer in the shelter at an elevation 
of about 5 inches above the surface of the bog; minimum thermometer in the open at the sur- 




FIG. 10.— Stution -1, Mather, Wis. 
Newly sanded, heavily vined. I'hotograph made in 1907. 

face of the marsh, also at elevations of 5 inches and 36 inches above the marsh; maximum 
thermometers similarly exposed at the surface and at 36 inches above the marsh, the thermome- 
ters at 5 inches and at 36 inches being fastened to a post; air thermograpli which rested on the 
surface of the soil; soil thermometers at depths of 3 inches and (i indies, respectively: soil 
thermographs, the bulbs of which were similarly exposed. 

Station 4 (Fig. 10), also a heavily sanded section, but the vines and vegetation relatively 
dense. This exposure may be considered as representing the best conditions prevaihng on the 
bog as reo;ards sandmg and draining. Efpiipment: Minimum thermometer in shelter at an 
elevation of about 5 inches above the surface of the bog; minimum thermometers in open, at 
the surface of the bog, and at an elevation of 5 inches; maximum thermometer at the surface 
of the marsh; an Assman aspiration psychrometer fastened to the shelter; soil thermometers 
at depths of 3 and 6 inches; soil thermograph, the bulb of wliich was placed in the soil at a 
depth of 3 inches; anemometer fastened to the top of shelter and attached to a single register 
inside, the cups of the anemometer being 4 feet 7 inches above the ground. 

Station 5 (Fig. 11), in an uncultivated portion of the bog, but close to the cultivated sec- 
tions. It had never been sanded, the soil being plain peat, and it had a dense growth of vines 



21 




Fm. U.— stiUiouo. JIiitlKT. Wi.v 
In uneiiltivated bog. Photograpli uiadi; in PJUil. 




Fig. 12.— Station 6, Mather, Wis. 
Old sandeil, heavily vined. Photograpli made in 190G. 



22 



and other vegetation, including numerous patches of sphagnum and wood moss. This location 
represents the poorest conditions on the cranberry marsh as regards cultivation and drainage, 
and it was consecjuently wetter than Stations 3 and 4. Equipment: Minimum thermometer 
in shelter at an elevation of about 5 inelies above the surface of the marsh; minimum thermom- 
eters in tlio open at the surface of tjie bog, and at an elevation of 5 inches; maximum thermom- 
eter at the surface of the bog; air thermograph placed in the open on the surface of the marsh; 
soil thermometers exposed at depths of 3 inches and 6 inches; soil thermographs, the bulbs of 
which were similarly exposed. During the season of 1907, the vines surrounding the soil 
instruments dietl out, and gradually changed from tlie conditions prevailing in 1906. This 
was clue to unavoidable trampling of the vines by the assistant who made the observations. 
With the purpose of maintaining the original conditions as far as possible, the exposures of 
these instruments were changed twice during August. 

Station 6 (Fig. 12), in a cultivated section which had been sanded about ISfls;, l)ut wliich 
had never been sanded a second time; so that a layer of peat an inch or two in thickness, 
formed from the decayed vegetation, covered the old sand. There was a dense growth of 




Fig. 13. — Stations 7 and 7a. Matlier. Wis. 
In scalped section and on moss adjoining. Photograph made in 1906. 

vines around the station and the drainage was similar to that of Statitm 5. Equipment: 
Minimum tliermometer in the shelter about 5 inches above the surface of the marsh; minimum 
thermometers in the open at the surface of the marsh, and at an elevation of 5 inches; maximum 
thermometer at the surface of the bog; soil thermometers at depths of 3 and 6 inches; soil 
thermograph, the bulb of which was exposed at a depth of 3 inches. The soil thermograph 
was fairly satisfactory for all months except October, when it became defective. 

Station 7 (Fig. 13), located outside the cultivated bog in a section of bare peat, scalped 
especially for the purpose in 1906, in the midst of a dense growth of sphagnum moss. This 
station was at the lower end of 1«he marsh, and consecjuently more damp than the cultivated 
sections. Equipment: Minimum thermometer in the shelter about 5 inches above the surface 
of the bog; minimum thermometers in the open at the surface of the peat, and at an elevation 
of 5 inches; maximum thermometer at the surftice of the peat; soil thermometers at depths of 
3 inches and 6 inches; soil thermograph, the bulb of wliich was exposed at a depth of 3 inches. 

Station 8 (Fig. 14), the reservoir. This station was in a ditch about 4 feet in depth, and 
from 20 to 25 feet wide, lying between the floating marsh on the west antl a dam on the east. 
Equipment: Water thermometer; soil tliermograph, with the bulb exposed in the water at a 



23 




Fig. 14.— Station 8, Mather. Wi.s. 

Reservoir .allowing; widr- flitch anri filiating bog. Observer taking an observation of water 
temperature. 




Fig. 16.— Stiition 9. Mather, Wis. 

In garden on upland. Photograph made in ia06. This station was supplied in 1907 with 
additional thermometers in instrument shelter and attached to the po.sts up to an elevation 
of 36 inches. 



24 



depth of about 12 inches. This instrument although officialh- known as a soil themiograpli 
might in this case properly be called a water thermograph. 

Station 9 (Fig. 15), over sandy loam in the garden in the rear of the dwelling on Long Island. 
It was established for the purpose of making some comparison between the conditions on hard 
ground and in the adjoining bog. The garden was planted, but well cultivated and dri.ined. 
Ecjuipment: Minimum thermometer in the shelter about 5 inches ajjove the surface of the 
soil; 6 minimum and 6 maximum thermometers facing soutli at the following elevations: Sur- 
face, 2J inches, 5 inches, 7^ inches, 12 inches, and 36 inches, also minimum thermometers at 
additional elevations of 10 inches and 15 inches; soil thermometers at depths of 3 and 6 inches. 

Station 10 (Fig. 16), tlie warehouse. Ecjuipment: Anemometer and sunshine recorder 
exposed on the cupola of the warehouse, about 50 feet above the marsh, and about 35 feet 
above the ground on the upland. These instruments were attached to a doid^le register in a 
room in the warehouse. The wind vane was exposed on a building near the warehouse. 

Equipment of the Berlin Station. — It is hardly necessary to go into details regarding the 
erpiipment at Berlin (Fig. 6). The investigation there was confined to a portion of the year 




Fm. 16. — Station 10, Warehouse, Mather, Wis. 
Anemometer on enjtola. Sunsliine reeorder on ridjre of roof. 

1906, with a rather incomplete set of instruments. The peat and muck in this marsh reaches 
to a depth of 20 to 26 feet, and there is a stretch of hard land on the immediate border about 
3 feet above the surface of the marsh. The soil of this hard land consists of yellow clay. A 
short distance beyond there is a gradual slope to ordinary dark soil. 

A portion of the equipment used in this discu.ssion follows. Station 1, which was almost 
on tlie edge of the bog, was provided with an instrument shelter in which were exposed maximum 
ami minimum thermometers and an air thermograph. There was also a rain gage close at 
hand. (Fig. 17.) 

Station 2, over a peat bog which had been carefully weeded before the observations were 
begun. Ecpiipment : Minimum thermometers exposed in the open at the surface aiul at an 
elevation of 5 and 36 inches, respectively, above the surface of the marsh. 

The sections around Stations 3 and 4, to an extent of about 40 feet scjuare, had been espe- 
cially sanded for use in the investigation. The marsh, as a whole, had a rank growth of vege- 
tation, and had never been sanded. At Station 3 were minimum thermometers exposed in the 
open at the surface and at 5 and 36 inches above the surface; also a soil thermometer at a 



25 




Fig. 17.— Fituh marsh, Berlin. \Vi^., showing oar track on bog, dwellings, warehouses, and 
shanties. Cross in iiliotograph shows location of Station 1 in I'Wii. 




Fig. IS.— Station 5, Fitch marsh, Berlin, Wis. In ferns and canebrakes. 



26 

depth of 3 inches. This station well represents the best conditions obtainable from oultivating 
and sanchng, and fair conditions as regards draining. Station 4 had the same character, 
except that it was slightly lower than Station 3, and consecjuentl}- wetter through poorer 
drainage. The equipment consisted of minimum thermometers exposed in the open at the 
surface and -5 inches above. Stations 2, 3, and 4 were situated in a line about 100 feet apart. 
The thermometer shelters at Stations 2 and 3 ma}' be seen in Figure 6, which gives a view of 
a considerable portion of the Berlin marsh at da\\-n. Xo shelter was used at Station 4. The 
shelters at the other stations on the bog were used for housing the recording portions of the soil 
thermographs iluring the short time that they were in operation. These instruments proved 
defective in 1906, and consequently the records have not been used. 

Station .5 (Fig. IS), in a section termed the "ferns," about 1,000 feet north of Stations 
2, 3, and 4. The equipment consisted of maximum and minimum thermometers placed at the 
surface of the bog and at an elevation of 5 inches, respectively. The upper thermometers here 
were not fastened to a post, but merely placed on top of a bed of vines and ferns, which were 
pushed down in a compact mass to provide a resting place for the instruments at the desired 
height. In all other instances at Mather and Berlin the instruments exposed at an elevation 
above the surface were attached to wooden supports. Station .5 was also provided with a soil 
thermometer at a depth of 3 inches. Some additional instruments were included in the equip- 
ment, at the various stations, but it seems imnecessary to refer to them. The object has been 
to present in this report merely such observations made at Berlin as niav supplement the more 
complete data at Mather. 

The thermometers used in this investigation were all carefully tested in the Instrument 
Division at Wa.shington before being shipped to the cranberry marshes: they were daily exam- 
ined in order to detect possible defects, and exchanges in the instruments were made occa- 
sionally between the various stations at both Mather and Berlin, so as to obviate the effect 
of any possible instrumental error. 

DISCUSSION OF THE PROBLEM. 

Minimum temperatures in shelters, and in the open, both at 5 inches above the surface. — In 
order to dete^-mine the relation existing between the readings of thermometers in shelters and 
those exposed in "the open," as are the instruments generally used by the cranberry grower, 
minimum thermometers were placed at various stations at blather, in "the open" at 5 inches 
above the surface, corresponding in elevation to the thermometers placed in the respective 
shelters. During the day the svirface of any solid upon which the sun shines becomes hotter 
than the air above it, because the solid is a much better absorber of heat than the air; while at 
night, especially when the sky is clear, the air loses its heat more slowly than a solid, such as 
vegetation or soil, because the air is a very poor radiator of heat. The readings of the instru- 
ments in the shelters indicate the true temperature of the air at the various stations, while the 
readings of the thermometers outside the shelters, strictly .speaking, represent the temperatures 
of the instruments themselves, but they may be considered to indicate approximately the tem- 
perature of the vines and plants at the height of 5 inches. It is probable that the temperature 
of the vegetation was even lower than that recorded b}- these exposed minimum thermometers. 
The differences, however, can not be large, because the exposed minimums often registered 
readings as low as 28° without apparent damage to the vegetation. It is quite impracticable 
to secure daily readings of the temperature of plants or leaves that may be comparable. The 
reading of the thermometers exposed in the open might properly be termed "sensible tempera- 
tures," but in this bulletin all such readings, whether maximmn or minimum, will be referred 
to as exposed readings, or readings in the open. 

Table 1 shows in detail the daily readmgs and differences at each station, and Table la 
shows the averages for the various months and for the season of 1907. The average difference 
for the entire season was least at Station 9 on the upland, 1.4°, where there was a clean soil and 
very little vegetation. The average difference on the bog was least at Station 3, 2.5°, also where 



•27 

the vegetation was thin; and at Station 7, 2.7°, over peat, in the scalped piece, but closely 
surrounded by sphagnum moss. The difference was greatest at Station 5, 3.6°, and at Station 
6, 3.7°, where the vegetation was dense. The average difference at Station 4 was 2.6° — but 
slightly greater than that at Station 3. This difference was not larger because the location of 
the thermometers exposed at the 5-iuch height at Station 4 was tliinly vined as compared 
with the other portions of that section. In fact, a close relation was founfl to exist between 
these differences and the density of vegetation. On account of the great radiation of heat from 
vegetation, the exposed minimums were relatively much lower where the vegetation was dense 
than where the soil was clean. At all stations the least difference usually occurred during the 
month of May, with an increase irregularly toward midsummer with increasing vegetation, and 
then a falling off, which was later followed by another maximum in October. The gains and 
losses were not uniform at the various stations, simply because there was a lack in uniformity 
in the changing of the vegetation. The conditions changed because there was trampling of 
the vines and grasses, more at some stations than at others, and for various other reasons. It 
is probable that if all the conditions as regards vegetation, soil, and moisture were identical for 
the whole bog, or even for the section in which the instruments were located, approximately 
the same differences would occur at each station on each night : Init the amounts of these differ- 
ences would probably change as the nights became longer or shorter, and as the character of 
the weather varied from day to day. iloreover, if a uniform relation existed during the entire 
season as regards vegetation, between the places of exposure of the outside thermometers and 
the location of the shelter itself, the relation between the various differences of the readings 

o 

inside and outside would not change materially. 

The reason for the great differences in October is not because of increasing vegetation, but 
rather in spite of a decrease. It is due to the fact that the nights were much longer and com- 
paratively cokl, thus permitting great loss of heat from the plants by radiation and conduction. 
The greatest difference at Station 2 was 6.5° on October 11 ; at Station 3, 4.7° on October 31 ; at 
Station 4, 6.3° on October 22; at Station 5, 9.9° on July 10; at Station 6,7.9° on July 16: at 
Station 7, 6.4° on May 18; and at Station 9, 7.2° on August 10. There were, on the other hand, 
many days when there was only a slight difference in the readings, and there were a few instances 
in wliich the outside thermometers read slightly higher than those exposed in the shelters. 
Wlien the difference was great at one station, it was usually relative^ great at the other stations: 
likewise, when there was but a slight difference at one point, a like condition prevailed at the 
other stations. On nights of slight differences the sky was invariably overcast, while clear to 
partly cloudy conditions with comparatively lugh barometer prevaUed when great tlifferences 
occurred, which fact indicates that radiation is the controlling factor. Formation of dew on 
the bulbs of the outside thermometers, followed by a freshening of the wind and consequent 
evaporation of the moisture, was occasionally the cause of low readings of certain of these 
instruments. Dew doubtless often formed and disappeared during the night without being 
observed. 

The mean depression of the outside thermometers below those in the shelters at the six 
stations on the bog for the entu-e season of 1907 was 3°, and, including the record at Station 9 on 
the upUnd, the depression for the same period was 2.8°. Prof. WiUis I. Milham, « in experiments 
conducted at WUliamstown, Mass., on thirty-sLx cold and generally cloudless nights in the 
winter of 1904-5, wliile the ground was covered with snow, found that the average difference 
between the readings of a minimum thermometer expo.sed in a shelter and one in the open was 
3.9°, and that the greatest difference on any one night was 7.8°. In making comparisons 
between these figures and the results at Mather over vegetation, it should be borne in mind 
that the latter are for the entire growing season without regard to the cloudiness and the tem- 
perature prevailmg. The average difference on dear nights at Mather no doubt equals that 
determined by Professor ^lilham. 

a Monthly Weather Review, July, 1905. 



28 

The temperature in the shelter on the upland at Station Imay be considered theWandard 
with which other temperatures observed at Mather during this investigation should be compared. 
However, the readings at Station 1 have not been included in Tables 1 and la, because it was 
first desired to determine the relation existing between shelter and exposed temperatm-es at the 
same elevation, ^j referring to Table 18, which will be discussed in detail in turn, it should be 
noted that there is a great difference between the shelter readings on the bog and on the upland, 
the difference varying with the character of the soil and vegetation, as in the case of the observa- 
tions in shelter and in open at the various stations, referred to above in connection with the 
discussion of Tables 1 and la. Where the differences were great between the readings in shelter 
and open, relatively large differences were noted between the readings in those shelters and the 
shelter at Station 1 ; while, on the other hand, at stations where smaller differences were observed, 
the shelter readings approached more nearly the shelter readings at Station 1. 

Table 1. — Minimum Temper.^tures in Shelter and i.n open .\t 5-inch Height, for Each Station, Together 

WITH the Difference between Readings, Mather, .Wis., 1907. 





Station 2. Station 3. 


Station 4. Station 5. Station 0. 


Station 7. 


Station 9. 


Day of 
montb. 


in 


I 


1 


i 


•d 

X 


a 




T3 
X 


I 

5 


to 


■d 
o, 

X 


1 

5 


a) 


•6 

X 


1 


1 


1 


i 

5 


1 


« 5 


MAY. 

1 


o 


e o 


e 


a 


" 


» 


• 


. : . 


• 


~ a 


' 


• 


B 


o e 


« 


. ' . ' . 


2 
















1 










3 


















1 










4 


























































6 












































1 














8 






























9 

























1. 




10 




































11 .. . 




































1 


12, 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 


36.7 

ei.o 

45.0 
36.0 
34.8 
35.0 
35 3 
33.0 
gl.i 
23.2 
43.8 
43.8 
42.5 
44.8 
45.0 
(') 

34.0 
38.9 
46.5 


35.2 
60.0 
45.0 
36.3 
34.1 
32.4 
32.0 
28.2 
18.0 
21 
44.0 
43 9 
40.2 
44.0 
45.2 
C) 
C) 
29.8 
36.0 
45.0 


-1.5 
-1.0 
0.0 
+0.S 
-0.7 
-2 6 
-3.3 
-IS 
-3.4 
-2.2 
+0.2 
+0.1 
-2.3 
-0.8 
+0.2 

-4.2 
-2.9 
-1.5 


37.3 

ei.6 

45.7 
37.0 
35.4 
40.3 
45.4 
36.8 
25. S 
25.7 
44.3 
44.3 
43.8 
45.3 
45.5 
C) 
C) 
38.0 
44.7 
48.0 


35.4 
59.6 
45.0 
36.7 
34.6 
38.4 
40.9 
32.6 
Sl.S 
22.8 
44.0 
43.9 
41.3 
44.0 
45.2 

34.9 
41.1 
45.8 


-1.9 
-2.0 
-0.7 
-O.S 
-0.8 
-1.9 
-i.5 
-4.2 
-4.0 
-2.9 
-O.S 
-0.4 
-2.5 
-1.3 
-O.S 

-3.1 
-3.6 
-2.2 


37.4 

en 

45.8 
37.0 
35.5 
40.3 
45.1 
36.3 
U.l 
2b. i 
44.5 
44.2 
43.5 
45.2 
45.7 
C) 
W 
37.2 
43.8 
47.8 


35.4 
59.0 
45.1 
37.0 
34.6 
37.3 
39.0 
32.0 
20.0 
22.3 
44.2 
44.0 
42.0 
44.1 
45.2 

C) 
32.5 
39.5 
45.9 


-2.0 
-2.4 

-0.7 

0.0 

-0.9 

-3.0 

-6.; 

-4.3 
-5.1 
-3.1 
-0.3 
-0.2 
-1.5 
-1.1 
-0.5 

-4.7 
-4.3 
-1.9 


37.0 
«/.« 
45.1 
36.7 
35.3 
36.0 
40.1 
36.6 
21.6 
22.2 
44.5 
44.0 
40.3 
45.0 
45.2 
(') 
C) 
36.0 
40.4 
47.6 


35.0 
58.9 
45.1 
36.9 
34.8 
33.0 
39.1 
31.0 
19.3 
17.0 
42.0 
43.7 
34.0 
43.8 
45.0 

m 

C) 

29.3 
36.0 
45.9 


-2.0 
-2.3 
0.0 
+0.S 
-0.5 
-3.0 
-1.0 
-5.6 
-2.3 
-5.2 
-2.5 
-0.3 
-6.3 
-1.2 
-0.2 

-6.7 
-4.4 
-1.7 


37.0 
60.9 
45.0 
36.8 
35.0 
32.5 
41.2 
3S.6 
24.8 
Si. 5 
44.1 
44.1 
43.3 
45.0 
45.2 
('') 

m 

38.5 
43.0 
47.9 


34.2 
57.2 
44.9 
37.0 
34.2 
33.0 
39.3 
32.3 
17.8 
19.8 
43.0 
44.0 
39.3 
43.9 
45.0 

m 

C) 
34.7 
39.0 
45.4 


-2.8 
-3.7 
-0.1 
+0.2 
-0.8 
+0.5 
-1.9 
-6.3 
-7.0 
-4.7 
-1.1 
-0.1 
-4.0 
-1.1 
-0.2 

-3.8 
-4.0 
-2.5 


36.7 
61.0 
45.0 
36.8 
35.1 
35.4 
39.8 
37.8 
21. S 
23.7 
44.0 
044.2 
"42.9 
044.9 
045.2 
(») 

m 

36.0 
40.9 

047.2 


35.1 

58.0 

44.9 

36.7 

34.3 

32.3 

33.4 

32.1 

18.9 

22.0 

43.9 

043.9 

O40.0 

O44.0 

045. 

C) 

m 

30.8 
37.0 
045.4 


-1.6 
-3.0 
-0.1 
-0.1 
-0.8 
-3.1 

-e.i 

-5.7 
-2.4 
-1.7 
-0.1 
-0.3 
-2.9 
-0.9 
-0.2 

-5.2 
-3.9 
-1.8 


37.4 
61.5 
45.0 
36.0 
35.0 
39.9 
46.0 
37.3 
26.8 
25. S 
44.1 
44.0 
43.4 
44.6 
45.1 
(0) 
C) 
38.8 
44.0 
47.6 


36.7 
59.8 
45.0 
36.0 
34.8 
39.1 
44.9 
35.0 
23.8 
2S.0 
44.2 
44.0 
41.8 
44.0 
45.1 
C) 

m 

36.3 
42.3 
46.8 


-0.7 
-1.7 

0.0 

0.0 
-0.2 
-0.8 
-1.1 
-2.3 
-3.0 
-2.3 
+0.1 

0.0 
-1.8 
-0.6 

0.0 

-2.5 
-1.7 
-0.8 


Means . 


38.9 


37.2 


-1.7 1 41.4 


39.3 


-2.1 1 41.2 


38.8 


-2.4 


39.7 


37.2 


-2.5 


40.4 


38.0 


-2.4 


39.9 


37.6 


-2.3 


41.2 1 40.1 


-1.1 



a Affected by water. 
Station 2. Sphagnum moss. 
Station 3. Newly sanded, thinly vined. 
Station 4. Newly sanded, heavily vined. 
Station 5. Feat with raoss, heavily vined. 



6 Under water. 
Station fi. Old sanded, heavily vined. 
Station 7. Scalped piece, bare peat. 
Station 9. Sandy loam on upland. 



Highest and lowest readings are in italics. Means are for 18 days. 



29 



Table 1. Minimlm Temperatures w Shelter and in Open at 5-inch Height, for Each Station, Together 
WITH THE Difference between Readings, Mather, Wis., 1907— Continued. 



Day of 
month. 



7 

8 

9 

10 

11 

12 

13 

1-1 

15 

16 

17 

18 

19 

211 

21 

22 

23 

24 

23 

2B 

27 

28 

29 

30 



Means . 45. 4 



31.7 
32.3 
54.0 
38.4 
41.8 
31.4 
47.0 
31.4 
35.9 
53.9 
44.1 
51.2 
37.3 
35.0 
38.7 
48.6 

ee.o 

52.5 
50.2 
45.2 
45.0 
61.2 
68.0 
53.9 
55.9 
46.0 
39.3 
41.2 
44.8 
51.3 



17.9 
29.4 
53.0 
35.2 
38.0 
17.9 
44.8 
g7.9 
32.5 
63.3 
39.1 
50.6 
34.4 
31.0 
35.0 
46.0 
6$. 9 
49.6 
46.8 
42.3 
41.4 
59.0 
53.9 
49.6 
53.3 
40.9 
35.2 
36.7 
42.6 
48.9 



-3.8 
-2.9 
-1.0 
-3.2 
-3.8 



Station 3. 



34.9 
37.0 
54.9 
42.7 
43.9 



-3.6 034.0 
-2.2 47.9 



-3.5 
-3.4 
-0.6 
-6.0 
-0.7 
-2.9 
-4.0 
-3.7 
-2.6 
-3.1 
-2.9 
-3.4 
-2.9 
-3.6 
-2.2 
-4.1 
-4.3 
-2.6 
-S.l 
-4.1 
-4.5 
-2.2 
■2.4 



35.0 
40.0 
54.6 
46.2 
63.0 
42.6 
39.9 
42.0 
54.0 
69.0 
68.0 
56.2 
51.0 
49.3 
61.8 
60.0 
56.0 
57.9 
48.1 
44.6 
44.3 
51.4 
56.9 



42.3 -3.1 -48.9 



31.0 
34.0 
52.3 
39.6 
39.7 
■■31.3 
47.5 
32.2 
37.4 
53.2 
42.2 
51.0 
39.6 
37.9 
39.3 
61.2 
65.8 
55.2 
53.3 
48.0 
46.5 
60.4 
67.7 
53.8 
66.3 
46.1 
42.0 
41.1 
48.9 
54.1 



3.9 
3.0 
2.6 
3.1 

4-S 
2.7 

0.4 

2.8 
-2.6 
-1.4 
-4.0 
—2.0 
-3.0 
-2.0 
-2.7 
-2.8 
-3.2 
-2.8 
-2.9 
-3.0 
-2.8 
-1.4 
-2.3 
-2.2 
-1.6 
-2.0 
-2.5 
-3.2 
-2.5 
-2.8 



Station 4. 



34.9 
36.1 
54.8 
41.8 
43.5 
aSS.4 
47.7 
35.1 
39.9 
54.6 
45.5 
52.9 
42.3 
39.4 
41.4 
52.9 
69.1 
56.9 
55.8 
49.8 
48.8 
61.5 
69.9 
55.2 
57.4 
47.9 
43.4 
43.8 
50.0 
65.5 



48.4 



SO.S 
33.0 
51.0 
39.0 
41.4 
"SO. 7 
46.0 
32.0 
36.2 
53.2 
41.7 
52.1 
39.1 
36.3 
39.0 
50.2 
65.4 
64.9 
52.5 
47.5 
46.1 
60.1 
57.1 
53.0 
56.9 
46.0 
40.9 
41.0 
48.0 
53.0 



-4.4 

-3.1 

-3.8 

-2.8 

-2.1 

-2.7 

-1.7 

-3.1 

-47 

-1.4 

-3.8 

-0.8 

-3.2 

-3.1 

-2.4 

-2.7 

-3.7 

•2.0 

-3.3 

■2.3 

■2.7 

1.4 

■2.8 

2.2 

1.6 

1.9 

2.5 

2.8 

2.0 

2.5 



Station I 



45.7 :-2.7 



44.6 
51.0 



41.1 
47.4 



1 


•a 
p, 

K 


o 


„ 


31.4 


26.2 


31.4 


27.9 


63.6 


46.9 


40.2 


36.0 


43.3 


41.5 


<'30.7 


026.8 


47.0 


43.8 


30.8 


26.5 


35.1 


30.6 


54.0 


53.0 


44.2 


38.4 


62.5 


61.0 


36.2 


32.4 


33.8 


29.6 


37.6 


34.0 


48.9 


45.5 ■ 


68.5 


61.5 


52.7 


48.9 ■ 


53.4 


48.7 - 


61.0 


42.4 - 


44.0 


40.3 - 


61.1 


59.6 - 


59.0 


56.2 - 


62.5 


49.5 - 


56.9 


53.1 - 


47.8 


45.7 - 


39.2 


34.0 - 


38.6 


35.2 - 



6.2 
3.5 
6.7 
5.2 
-1.8 
3.9 
3.2 
-4.3 
-4.6 
-l.O 
-5.8 
-1.6 
-3.8 
■4.2 
■3.6 
■3.4 
■6.0 
-3.8 
■4.7 
■*.« 
■3.7 
■1.5 
■3.8 
3.0 
2.8 
2.1 
5.2 
3.4 
3.5 
3.6 



Station 6. 



-3.9 



36.0 
35.0 
63.6 
40.3 
44.0 
aSS.O 
47.7 
34.3 
38.3 
54.3 
45.2 
62.3 
39.4 
33.0 
39.5 
60.4 
68.0 
55.0 
63.4 
47.8 
46.8 
61.1 
60.0 
53.9 
56.2 
48.3 
40.8 
40.5 
47.8 
54.2 



35.3 
29.8 
47.0 
36.5 
41.5 
ai8.2 
44.0 
29.4 
33.9 
52.9 
40.7 
50.2 
34.8 
33.0 
36.1 
46.8 
64.0 
50.6 
47.5 
43.4 
42.4 
59.1 
56.3 
50.8 
53.2 
43.8 
35.1 
37.5 
42.8 
48.7 



-0.7 
5.2 
-6.5 
-3.8 
-2.5 
-3.8 
-3.7 
-4.9 
-4.4 
-1.4 
-4.5 
-2.1 
-4.6 
0.0 
-3.4 
-3.6 
-4.0 
-4.4 
-6.9 
-4.4 
-4.4 
-2.0 
-3.7 
-3.1 
-3.0 
-4.5 
-5.7 
-3.0 
-5.0 
-5.5 



Station 7. 



-3.8 



34.5 

34.8 

53.5 

40.3 

43.3 

31.1 

47.5 

31.4 

36.0 

63.9 

44.8 

53.0 

37.3 

34.6 

38.0 

49.5 

69.0 

65.0 

54.0 

46.0 { 

45.0 

61.1 

59.2 

63.4 

66.2 

48.0 

38.2 

39.8 

46.1 

53.1 



46.3 



28.7 
30.7 
50.0 
36.6 
41.5 
S7.t 
45.1 
27.9 
32.0 
53.0 
40.1 
61.4 
33.6 
31.1 
34.8 
46.6 
65.9 
51.0 
49.3 
42.2 
41.8 
59.8 
56 
49.6 
53.5 
46.0 
35.0 
36.8 
43.0 
49.4 



-5.8 
-4.1 
-3.5 
-3.7 
-1.8 
-4.0 
-2.4 
-3.6 
-4.0 
-0.9 
-4.7 
-1.6 
-3.7 
-3.5 
-3.2 
-2.9 
-3.1 
-4.0 
-4.7 
-3.8 
-3.2 
-1.3 
-3.2 
-3.8 
-2.7 
-2.0 
-3.2 
-3.0 
-3.1 
-3.7 



Station 9. 



43.0 -3.3 



34.5 
36.2 
55.1 
41.6 
43.8 
S3.0 
47.3 
33.5 
39.2 
54.5 
46.0 
53.0 
42.9 
37.5 
42.0 
53.8 
68.0 
57.3 
66.1 
50.1 
48.6 
61.7 
59.8 
54.1 
57. 5 
48.1 
44.5 
43.9 
51.1 
56.8 



48.4 



32.2 
32.8 
53.8 
40.4 
42.9 
31.5 
46.6 
31.8 
37.9 
53.4 
43.7 
62.5 
41.1 
36.1 
41. a 
52.0 
66.5 
55.7 
51.9 
47.9 
46.6 
60.6 
57.5 
53.2 
56.5 
47.2 
42.8 
42.1 
49.8 
54.1 



46. S 



Station 2. .Sphagnum moss. 

Station 3. Newly sanded, thinly vined. 

Station 4. Newly sanded, heavily vined. 

Station 5. Peat with moss, heavily vined. 



" .\fTected by water. 



Station 0. Old sanded, heavily vined. 
Station 7. Scalped piece, bare peat. 
Station 9. Sandy loam on upland. 



-2.3 

-3.4 

-1.3 

-1.2 
-0.9 
-1.5 
-0.7 
-1.7 
-1.3 
-1.1 
-2.3 
-0.5 
-1.8 
-1.6 
-1.0 
-l.S 
-1.5 
-1.6 
-1.2 
—2.2 
-2.0 
-1.1 
-2.3 
-0.9 
-1.0 
-0.9 
-1.7 
-1.8 
-1.3 
-2.7 



-1.6 



Highest and lowest readings are in italics. 



30 

Table 1. — Minimum Temperatires ix Shelter and ix Opex at 5-ixch Height, for Each Station-, Together 
WITH THE DiFFEREXCE BETWEEN READINGS. Mather. Wis.. 1907 — Continued. * 





Station 


2. ' Station 3. 


Station 4. 


Station 


3. 


Station 


5. 


station 


1 Station 


J. 


Day of 
month. 


o 
OD 


1* 


. 
g 

1 1 i 

i 1 1 

Q 1 m 




i 

5 


1 

QD 


■d 

X 


s 

a 
S 


1 
m 


•d 


8 

B 

2 
& 

a 


1 

GO 




i 



S 
1 


•d 

X 

K 


i 




2 
5 


1 




JULY. 


= 


e 


e 




o 


o 


o 


e 


a 


e 





, 





„ 





« 


a 


„ 





1 


55.0 


52.0 


-3.0 58.8 


57.1 


-1.7 


58.5 


57.0 -l.S 


58.8 


55.9 


-2.9 


58.7 


54.3 


-4.4 


59.0 


58.1 


-0.9 


59.0 


57.8 


-1.2 


2 


SI. 4 


29.4 


-3.0 SS.i 


S4.8 


-3.6 


S7.4 


34. S -3.1 


Sl.l 


tT.9 


-3.3 


So. I 


i9.0 


-6.2 


SS.O 


29.7 


-3.3 


S6.9 


SS.9 


-s.o 


3 


41.4 


38.5 


-2.9 48.0 


45.0 


-3.0 


47.1 


44.7 


-2.4 


40.2 


36.2 


-4.0 


44.1 


38.3 


-5.8 


43.0 


39.2 


-3.8 47.7 


45.0 


-2.7 


4 


47.3 1 44.7 


-2.6 51.6 


48.9 


-2.7 


50.8 


48.8 


-2.0 


50.8 


43.9 


-6.9 


49.9 


46.0 


-3.9 


47.4 


45.0 


-2.4 


51.0 


49.5 


-1.5 


5 


60.6 59.4 


-1.2 


61.3 


60.3 


-1.0 


61.2 


60.5 


-0.7 


60.8 


59.7 


-1.1 


61.0 


61.5 


+0.0 


OS7.5 


054.7 


-2.8 


61.0 


60.0 


-1.0 


6 


55.0 52.8 


-2.2 


59.0 


57.0 


-2.0 


58.0 


56.2 


-1.8 


54.8 


52.0 


-2.8 


56.8 


52.1 


-4.7 


"55.5 


"52.1 


-2.8 


58.2 


57.3 


-0.9 


7 


46.3 . 43.2 


-3.1 1 51.2 


48.0 


-3.2 


50.8 


48.0 


-2.8 


50.8 


42.5 


-8.3 


49.0 


43.7 


-5.3 


48.9 


46.3 


-2.6 


50.4 


49.0 


-1.4 


8 


50.0 ! 47.0 


-3.0 56.9 


53.1 


-3.8 


55.0 


50.4 


-4-6 


54.3 


49.4 


-4.9 1 55.8 


50.0 


-5.8 


57.0 


53.4 


-3.6 


58.1 


56.2 


-1.9 


9........ 


54.1 j 51.0 


-3.1 61.0 


57.1 


-3.9 i 60.0 


56.1 


-3.9 


56.6 


51.9 


-4.7 


57.5 


51.4 


-6.1 


56.9 


52.5 


-4.4 


60.4 


59.9 


-0.5 


10 


45.2 ; 42.3 


-2.9 50.8 


47.8 


-3.0 1 49.8 


47.7 


-2.1 


50.9 


41.0 


-9.9 


47.0 


42.2 


-4.8 


45.9 


42.2 


-3.7 


50.0 


47.6 


-2.4 


11 


59.8 1 60.2 


+0.4 60.6 


60.3 


-O.S 


60.8 


60.0 


-0.8 


61.1 


60.1 


-1.0 


61.5- 


59.9 


-1.6 


61.0 


60.1 


-0.9 


61.0 


60.1 


-0.9 


12 


44.5 


42.3 


-2.2 49.5 


46.5 


-3.0 


48.4 


46.1 


-2.3 


46.2 


39.9 


-6.3 


46.3 


41.8 


-4.5 


45.0 


41.5 


-3.5 


49 2 


47.0 


-2.2 


13 


47.0 


44.3 


-2.7 53.0 


50.0 


-3.0 


51.6 49.2 


-2.4 


48.4 


44.0 


-4.4 


51.3 


45.9 


-5.4 


49.9 


45.9 


-4.0 


52.0 


49.4 


-2.6 


14 


60.9 


56.4 


-4.5 62.2 


59.0 


-3.2 


62.0 59.1 


-1.9 


61.2 


56.8 


-4.4 


61.5 


56.8 


-4.7 


61.3 


58.2 


-3.1 


62.0 


60.0 


-2.0 


15 


6S.0 


67. S 


-0.2 6S.S 


ea.s 


-0.5 


6S.1 67.8 


-O.S 


68. « 


67.1 


-1.1 


68.0 


66.7 


-1.3 


68.0 


68. i 


+0.« 


68.1 


68.0 


-0.1 


16 


49.3 


46.3 


-3.0 53.1 


50.0 


-3.1 


52.2 i 50.0 


-2.2 


51.1 


45.3 


-5.8 


54.4 


46.5 


-7.9 


48.9 


46.1 


-2.8 


51.7 


50.4 


-1.3 


17 


4S.3 


45.0 


-3.3 55.1 


51.3 


-3.8 


52.1 49.0 


-3.1 


50.0 


45.0 


-5.0 


53.2 


47.3 


-5.9 


54.0 


47.9 


-6.1 


56.0 


53.9 


-2.1 


18 


46.9 


44.5 


-2.4 51.0 


47.6 


-3.4 


50.1 47.8 


-2.3 


45.8 


42.6 


-3.2 


47.9 


43.8 


-4.1 


46.0 


43.1 


-2.9 1 50.2 


49.0 


-1.2 


19 


52.8 


51.8 


-1.0 57.1 


54.8 


-2.3 


56.8 54.8 


-2.0 


5.3.9 


51.0 


-2.9 


56.0 


51.5 


-4.5 


54.1 


51.6 


-2.5 I 56.8 


55.1 


-1.7 


20 


52.9 50.1 


-2.8 59.8 


56.7 


-3.1 


59.0 55.1 


-3.9 


562 


51.3 


-4.9 


58.0 


52.5 


—5.5 


58.6 


56.2 


-2.4 1 60.3 


58.9 


—1.4 


21 


62.0 j 60.2 


-1.8 65.0 


63.2 


-1.8 


64.8 


63.0 


-1.8 


62.2 


59.9 


-2.3 


63.0 


60.0 


-3.0 


62.8 


61.1 


-1.7 1 64.8 


64.0 


-0.8 


22 


60.0 1 57.3 


-2.7 63.0 


62.0 


-1.5 


63.2 


61.4 


-1.8 


64.0 


61.9 


-2.1 ' 54.5 


62.3 


-2.2 


"61.3 


"58.5 


-2.8 ' 63.9 


63.0 


-0.9 


23 


54.0 1 48.9 


-S.I 53.2 


50.1 


-3.1 


52.2 


48.8 ; -3. 4 


050.3 


045.9 


-4.4 051.0 


O40.7 


-4.3 


050.1 


047.3 


-2.8 52.1 


49.9 


—2.2 


24 


61.0 58.7 


-2.3 64.0 


60.0 


-4.0 


64.0 


59.8 


-4.2 


"61.5 


"57.1 


-4.4 062.2 


057.9 


-4.3 


061.3 


058.5 


-2.8 ' 65.0 


63.1 


-1.9 


25 


52.8 49.5 


-3.3 53.7 


50.9 


i-2.8 


53.0 1 50.8 


-2.2 


ooO.l 


"45.7 


-4.4 "50.8 


"46.5 


-4.3 


"49.9 


047.1 


-2.8 53.0 


51.6 


-1.4 


26 


46.3 42.3 


-4.0 49.4 


47.0 


-2.4 


48.5 46.3 


-2.2 


046.5 


042.1 


-4.4 047.2 


"42.9 


-4.3 


"46.3 


"43.5 


-2.8 49.0 


47.8 


-1.2 


27 


44.9 41.0 


-3.9 46.9 


43.4 


-3.5 


45.9 ' 43.0 


-2.9 


45.0 


40.0 


-5.0 043.2 


038.9 


-4.3 


"42.3 


"39.5 


-2.8 1 44.9 


43.4 


-l..i 


28 


56. 6 55. 3 


-1.3 58.9 i 57.0 


-1.9 


59.2 56.5 


-2.7 


57.5 


53.2 


-4.3 58.4 


54.0 


-4.4 


056.2 053.4 


-2.8 59.0 


56.9 


-2.1 


29 


51.3 48.1 


—3.2 ; 56.1 


54.0 


-2.1 


55.9 53.2 


-2.7 


55.0 


51.5 


—3.5 56.1 


53.0 


-3.1 


56.5 55.0 


-1.5 ' 56.1 


55.0 


-1.1 


30 


46.5 45.0 


-1.5 51.0 


48.1 


-2.9 


49.9 46.4 


-3.5 


50.0 


41.6 


-8.4 48.9 


43.2 


-5.7 


49.5 45.9 


-3.6 ! 52.0 


49.9 


-2.1 


31 


52.9 48.5 


-4.4 1 56.1 


53.1 


-3.0 


55.2 52.0 


-3.2 


54.4 


50.0 


-4.4 55.0 49.8 

1 1 


-5.2 


55.3 53.0 


-2.3 1 57.0 


55.7 


-1.3 


Means.. 


51.8 49.2 


-2.6 j 55.6 j 53.0 


-2.6 


54.9 52.4 1-2.5 ! 53.1 


48.8 


-4.3 ' 53.8 49.6 


-4.2 


53.0 50.2 


-2.8 1 55.4 


53.8 


-1.6 



o Estimated: actnal readings valueless on account of reflowing or heavy rains. 



Station 2. Spagnum moss. 
Station 3. Newly sanded, thinly vined. 
Station A. Newly sanded, heavily vined. 
Station 5. Peat with moss, heavily vined. 

Highest and lowest readings are in italics 



Station 6. Old Sanded, heavily vined. 
Station?. Scalped piece, bare peat. 
Station 9. Sandy loam on upland. 



31 



Table 1— Minimi M Temperati RES IN Shelter ank ix Open" at o-inch Height, for Each Statiox 
wiTH THE Difference between Readinc.s, Mather, Wis., 1907 — Continued. 



Together 



Day of 
month. 



Station 2. 



Station 3. 



£ ^ 



AUGUST. 


^ 

o 


1 


51.7 


2 


42.8 


3 


43.1 


4 


se.B 


5 


58.9 


6 


48.1 


7 


51.3 


S ' 


53.0 


9 


52.0 


10 


67.0 


U 


7/. 6 


12 


43.4 


13 


45.6 


14 


49.3 


15 


53.6 


16 


59.4 


17 


47.0 


18 


51.0 


19 


65.0 


20 


38.9 


21 


39.8 


•» 


37.7 


23 


51.2 


24 


44.7 


25 


38.1 


26 


46.4 


27 


55.1 


28 


54.0 


29 


47.6 


30 


63.5 


31 


54.9 



Means. 



47.0 
39.1 
40.0 
34.1 
37.9 
46.0 
48.2 
51.0 
48.9 
54.6 
70. S 
40.1 
42.0 
46.0 
49.6 
57.7 
43.4 
47.7 
64.7 
34,1 
35.7 
33.9 
47.2 
41.0 
Sg.7 
42.5 
56.5 
49.9 
43.7 
62.3 
52.4 



2.0 56.0 
-3. 1 54. 6 



-4.7 


54.9 


-3.7 


45.3 


-3.1 


47.9 


-2.1 


44.9 


-1.0 


59.1 


-2.1 


53.4 


-3.1 


57.0 



2.4 

1.1 

3.3 

3.6 

3.3 

-4.0 

1.7 

-3.6 

3.3 

-0.3 

-4.8 

-4.1 

-3.8 

-4.0 

-3.7 

-5.4 

-3.9 

-4.1 
-3.9 
-1.2 
-2.5 



50.1 



47.1 



60.1 
71.9 
50.4 
49.8 
53.0 
56.4 
61.7 
51.1 
55.5 
65.0 
43.3 
49.0 
4^.5 
51.7 
50.9 
44.3 
50.4 
55,8 
57.0 
51.6 
63.8 
57.6 



51.2 
43.3 
44.5 
42.1 
58.3 
51.0 
54.8 
54.0 
51.8 
58.0 
67.4 
46.7 
46.8 
50.6 
53.4 
60.3 
48.6 
52.3 
65.0 
39.8 
44,6 
S9.S 
48.3 
47.6 
40.8 
47.8 
55.0 
63.4 
49.5 
63.3 
55.8 



Station 4. 



-3.7 
-2.0 
-3.4 

-2.8 
-0.8 
-2.4 
-2.2 
-2.0 
-2.8 
-2.1 

-4.S 

-3.7 

-3.0 

2.9 

-3.0 

-1.4 

-2.5 

3.2 

0.0 

-3.5 

4.4 

3.0 

3.4 

3.3 

3.5 

2.6 

0.8 

-3.6 

-2.1 

-0.5 

-1.8 



51.2 -2.6 



53.4 
45.0 
47.0 
43.2 
59.1 
52.1 
56.4 
55.6 
54.1 
59.5 
70.0 
48.6 
48.9 
52.7 
56.0 
61.5 
49.8 
54.2 
65.0 
42.0 
47.7 

41.4 

54.5 
50.8 
43.4 
49.8 
55.6 
56.0 
51.1 
64.4 
57.6 



53.1 



49.1 
42.5 
43.8 
39.7 
58.2 
49.0 
54.0 
55.3 
51.9 
57.8 
68. S 
44,0 
45.9 
50.0 
53.0 
60.2 
47.6 
51.5 
64.8 
38.5 
43.6 

SS.4 

51.1 
46.8 
38,7 
47.0 
55.2 
53.5 
48,6 
63.7 
55.4 



50.6 



•4.3 
-2,5 
-3.2 
-3.5 
-0.9 
-3.1 
-2.4 
-0.3 
-2.2 
-1.7 
-1.7 
-4.6 
-3.0 
-2.7 
-3.0 
-1.3 
-2.2 
-2.7 
-0.2 
-3.5 
-4.1 
-3.0 
-3.4 
-4.0 



Station 5. 



51.0 
44.3 
45.8 
S6.9 
59,0 
47.9 
56.1 
52.0 
51.5 
53.8 
7/. 5 
45.2 
44,0 
48.3 
34.5 
61.0 
42. S 
50.2 
64.9 
40.6 
40.7 
37.5 
50.1 
49.6 



—4.7 I 38,2 



-2.8 
0.4 
2.5 
-2.5 
-0.7 
-2.2 



-2.5 



45.0 
55.7 
54.4 
46.8 
63.7 
54.9 



44.0 
40.9 
41.9 
S3.0 
58.0 
44.8 
54.0 
50.1 
48.0 
53.0 
69.0 
41.0 
40.6 
45.0 
50.2 
58,6 
43,6 
46.7 
64.8 
34.8 
35.6 
33.6 
46.1 
44.3 
33.3 
41.0 
55.6 
50.5 
44.0 
62.6 
52.7 



Station 6. 



-7.0 
-3.4 
-3.9 
-3.9 
-1.0 
-3.1 
-2.1 
-1.9 
-3.5 
-2.8 
-2.3 
-4.2 
-3.4 
-3.3 
-4.3 
-2.4 
+0.S 
-3.5 
-0,1 
-5.8 
-5.1 
-3.9 
-4.0 
-5.3 
-4.9 
-4.0 
-0.1 
-3.9 
-2.8 
-1.1 
-2.2 



50.3 I 47.1 



51.6 
44.0 
46.0 
41,5 
39.0 
49.9 
56.3 
55.0 
53.4 
59.1 
70.0 
50.0 
47.0 
50.5 
55.5 
61.0 
49.2 
54.1 
64.9 
41.0 
46.8 
40.0 
51.9 
50.8 
41.2 
47.9 
57.5 
55.4 
49.6 
61.8 
56.5 



43.3 
41.5 
41.8 
36.0 
57.3 
45.9 
53.4 
51.1 
49.0 



-6.1 
-2.5 
-4.2 
-5.5 
-1.5 
-4.0 
-2,9 
-3.9 
-4.4 



.5 -3.6 



-3.2 



52.1 



68. S 
43.2 
42.0 
4C.1 
51.1 
58.2 
44.1 
48.7 
64.3 
36.3 
40.4 
SS.S 
47.3 
46.5 
33.6 
43.8 
35.6 
51.3 
45.3 
62.7 
53. S 



-1.5 
-6.8 
-5.0 

-4.4 
-4.4 
-2.8 
-3.1 
-5.4 
-0.6 
-4.7 
1-6.4 
i-4.7 
-4.6 



5 1-4.; 



48.3 



-5.6 
-4.1 
-1.9 
-4.1 
-4.3 
+0.9 
-3.0 



51.4 
44.8 
46.9 
S3.0 
59.2 
48.1 
56.1 
55.0 
51.3 
57.0 
71. S 
48. 
44.8 
49.1 
54.8 
61.3 
48.7 



47.1 
43.0 
45.0 
SS.S 
58.0 
45.4 
34.4 
31.5 
48.8 
54.3 
69. « 
42.7 
41.4 
46.1 
50.6 
59.3 
44.3 



5 



52.0 I 48.9 
65.0 65.0 
44.8 43.5 
41.8 I 38.8 
39.0 I 33.6 
51.2 48.0 



"51.7 
42.6 
48.4 
56.0 
36.0 
50.1 
64.0 

"55.7 



049.2 
38.3 
44.8 
55.8 
52.6 
48.6 
62.1 
33.8 



-3.8 ' 51.6 



4.3 

1.8 

1.9 

2.2 

1.2 

2.7 

1.7 

3.5 

2.5 

2.7 

2.0 

5.S 

3.4 

3.0 

4.2 

-2,0 

-4.4 

-3.1 

0.0 

-1.3 

-3.0 

-3.4 

-3.2 

-2.5 

-4.3 

-3.6 

-0.2 

-3.4 

-1.3 

-1.9 

-1.9 



54.9 
45.0 
46.8 
38.9 
59.0 
53.5 
56.7 
55.0 
53.4 
59.2 
73. « 
51.0 
49.3 
52,7 
56.1 
61.3 
51.2 
36.0 
65.0 
42.5 
46.5 
42.6 
53.5 
52.5 
46.0 
50.0 
55.2 
57.0 
51.4 
62.3 
58.0 



52.8 
43.9 
46.5 
37.7 
58,2 
51.3 
55.1 
53.6 
51.9 
32.0 
70.9 
49,0 
47.5 
50.4 
54.0 
61.3 
49.0 
54.2 
65.0 
40.8 
44.7 
40.8 
52.4 
50.0 
44.2 
49.0 
57.0 
54.9 
50.5 
63.8 
56.9 



-2.1 
-1.1 
-0.3 
-1.2 
-0.8 
-2.2 
-1.6 
-1.4 
-1.5 
-7.1 
-2.7 
-2.0 
-2.0 
-2.3 
-2,1 

0.0 
-2.2 
-1.8 

0.0 
-1.7 
-1.8 
-1.8 
-1.1 
-2.5 
-1.8 
-1.0 
+1.8 
-2.1 
-0.9 
-1-1.5 
-1.1 



49.0 



-2.0 : 53.4 



51.9 



-1.5 



a Estimated; actual readings valueless on account of reflowing or lieavy rains. 



Station 2. Spliagnum moss. 
Station 3. Newly sanded, tliinly vined. 
Station 4. Newly sanded, lieavily vined. 
Station o. Peat with moss, heavily vined. 

Highest and lowest readings are in italics 

51936"- -Bull, T— 10 3 



Station 6, Old sanded, heavily vined. 
Station 7. Scalped piece, bare peat. 
Station 9. Sandy loam on upland. 



32 

Table 1. — ^Minimum Temperatures in Shelter and in open at 5-incii Height, for Each Station^Togethbr 
WITH the Difference between Readings, Mather, Wis., 1907 — Continued. 



Day of 
month. 



SEPTEM- 
BER. 

1 

2 

3 

4 

5 

fi....'... 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

Means 



Station 2. 



65.0 
47.0 
45.1 
45.1 
40.9 
38.0 
56.8 
55.9 
36.5 
35.5 
42.2 
40.5 
44.0 
59.4 
58.0 
65.5 
47.6 
57.9 
60.6 
58.8 
35.0 
29.0 
42.8 
43.3 
25.4 
29.3 
32.1 
38.7 
28.9 
S5.1 



60.9 
41.9 
40.5 
44.7 
35.5 
33.4 
54.9 
55.8 
30.3 
30.3 
37.4 
36.6 
40.3 
57.3 
53.6 
612 
43.6 
66.0 
58.0 
57.2 
29.5 
22.7 
37.0 
40.3 
19.5 
24.7 
27.0 
34.6 
24.6 
18.8 



Station 3. 



-4.1 
-5.1 
-4.6 
-0.4 
-5.4 
-4.6 
-0.9 

-as 

-6.2 
-5.2 
-4.8 
-3.9 
-3.7 
-2.1 
-4.4 
-1.3 
-4.0 
-1.9 
-2.6 
-1.6 
-5.5 
-6.3 
-5.8 
-3.0 
-5.9 
-4.6 
-5.1 
-4.1 
-4.3 
-6.3 



67.1 
52.9 
50.2 
53.4 
44.5 
41.0 
55.6 
56.7 
39.8 

=37.8 
46.6 
44.6 
47.0 
59.7 
60.1 
65.8 
52.5 
58.3 
61.1 
59.5 
38.5 

<"31. 1 
44.2 
4.3.3 

028.0 

133.8 
33.7 
39.0 
30.0 
26.6 



63.8 
50.4 
47.9 
61.0 
4.3.0 
37.9 
56.7 
56.6 
37.1 

"35.3 
43.3 
42.2 
46.1 
57.4 
57.3 
64.8 
49.5 
57.8 
59.6 
56.7 
36.4 

"28.6 
41.4 
42.0 

a26. 6 

031.3 
31.2 
37.2 
27.7 
23. i 



S.S 
-2.5 
-2.3 
-2.4 
-1.5 
-3.1 
+0.2 
-0.1 
-2.7 
-2.5 
-2.3 
-2.4 
-0.9 
-2.3 
-2.8 
-1.0 
-3.0 
-0.5 
-1.5 
-2.8 
-2.1 
-2.5 
-2.8 
-1.3 
-2.5 
-2.6 
-2.5 
-1.8 
-2.3 
-3.2 



67.5 
52.3 
49.5 
52.7 
43.9 
40.7 
55.8 
66.0 
39.7 

137.2 
44.6 
43.3 
46.6 
60.1 
59.7 
66.0 
61.7 
58.4 
61.0 
59.2 
37.5 

130.5 
43.9 
43.0 

127.4 

033.2 
33.6 
38.7 
29.7 
26.0 



63.4 
49.6 
46.0 
50.0 
42.8 
38.2 
65.9 
56.6 
36.6 

135.2 
42.3 
40.2 
43.8 
57.3 
56.6 
6i.8 
48.9 
67.6 
59.6 
57.3 
34.0 

128.5 
40.4 
42.7 

125 4 

131.2 
31.3 
37.9 
27.4 



-3.1 

-2.7 
-3.5 
-2.7 
-1.1 
-2.5 
-1-0.1 
-1-0.6 
-4.1 
-2.0 
-2.3 
-3.1 
-2.8 
-2 8 
-3.1 
-1.2 
-2.8 
-0.8 
-1.4 
-1.9 
-3.5 
-2,0 
-3.5 
-0.3 
-2.0 
-2.0 
-2.3 
—0.8 
-2.3 
-3.6 



Station 5. 



66.5 
50.0 
47.0 
52.1 
43.4 
35 7 
65.9 
153.6 
36.0 
135.1 
41.0 
40.5 
43.3 
69.5 
56.9 
65.6 
46.8 
58.0 
60.8 
69.2 
35.6 
26.2 
43.7 
42.7 
25.0 
26.4 
30.0 
38.5 
26.3 
21.7 



61.7 
45.5 
41.3 
48.8 
41.3 
32.6 
56.5 

150.8 
33.7 

132.3 
36.6 
37.0 
39.7 
54.9 
53.0 
64.5 
43.5 
66.1 
58.8 
56.2 
31.1 
19.7 
39.0 
41.7 
20.6 
22.6 
26.1 
36.9 
23.3 
16.6 



-4.8 
-4.5 
-5.7 
-3.3 
-21 
-3.1 
-0.4 
-2.8 
-2.3 
-2.8 
-4.5 
-3.5 
-3.6 
-4.6 
-3.9 
-1.1 
-3.3 
-1.9 
-2.0 
-3.0 
-4.5 
-5.5 
-4.7 
-1.0 
-4.4 
-3.8 
-3.9 
-1.6 
-3.0 
-6.1 



Station 6. 



66.6 
50.6 
47.7 
52 9 
44.0 
38.6 
66.9 
56.7 
39.5 
136.4 
42.6 
43.4 
45.6 
69.7 
58.7 
66.5 
49.0 
58.0 
60.7 
69.2 
36.8 
27.6 
43.9 
43.1 
26.2 
29.5 
31.13 
38.6 
28.0 
24.6 



62.4 
45.7 
42.5 
50.6 
42.3 
34.9 
56.5 
56.4 
34.4 
133.2 
38.7 
38.4 
41.7 
54.8 
54.8 
64-4 
44.0 
67.8 
68.8 
56.2 
31.5 
20.0 
39.3 
41.6 
20.6 
23.7 
27.4 
37.5 
24.6 
18.1 



-4.2 
-4.9 
-6.2 
-2.3 
-1.7 
-3.7 
-0.4 
-0.3 
-6.1 
-3.2 
-3.9 
-5.0 
-3.9 
-4.9 
-3.9 
-1.1 
-5.0 
-0.2 
-1.9 
-3.0 
-5 3 
-7.6 
-4.6 
-1.5 
-4.6 
-6.8 
-3.9 
-1.1 
-3.4 
-6.5 



Station 7. 



66.2 
51.5 
49.5 
52.5 
43.0 
37.1 
55.9 
66.7 
39.6 
33.9 
43.2 
39.5 
44.6 
59.3 
58.3 
65.6 
48.0 
58.1 
60.6 
59.4 
35.3 
27.0 
44.0 
43.0 
26.5 
28.8 
31.2 
38.5 
28.0 
24.0 



62.8 
49.1 
46.4 
61.5 
39.4 
34.6 
55.6 
56.8 
37.4 
31.6 
38.9 
37.0 
41.1 
6t.O 
55.1 
64.8 
44.8 
68.3 
59.5 
67.9 
31.1 
22.7 
41.7 
42.9 
25.0 
26.0 
28.1 
37.0 
26.0 
20.5 



-3.4 
-2.4 
-3 1 
-1.0 
-3.6 
-2.6 
-0.3 
-hO.l 
-2.1 
-2.3 
-4.3 
-2.6 
-3.5 
-S.S 
-3.2 
-0.8 
-3.2 
+0.2 
-1.1 
-1.6 
-4.2 
-4.3 
-2.3 
-0.1 
-1.5 
-2.8 
-3.1 
-1.5 
-2.0 
-3.5 



Station 9. 



69.6 
62.6 
50.1 
52.7 
43.8 
40.9 
56.0 
56.7 
39.5 
38.2 
46.6 
46.3 
48.0 
57.0 
60.0 
65.4 
52.3 
58.0 
60.6 
59.5 
37.6 
30.2 
43.6 
43.2 
27.6 
31.6 
33.3 
38.8 
29.8 
26.7 



66.7 
51.4 
48.9 
52.0 
43.6 
39.4 
56.6 
56.7 
38.4 
36,8 
45.4 
44.8 
46.3 
67.4 
57.5 
64.8 
50.4 
57.7 
59.9 
58.6 
35.3 
27.8 
42.4 
42.4 
26.3 
29.3 
31.6 
38.0 
28.6 
24-7 



-2.9 
-1.2 
-1.2 
-0.7 
-0.2 
-1.5 
+0.6 
0.0 
-1.1 
-1.4 
-l.I 
-1.5 
-1.7 
+0.4 
-2.5 
-0.6 
-1.9 
-0.3 
-0.7 
-0.9 
-2.3 
-2.4 
-1.1 
-0.8 
-1.3 
-2.2 
-1.7 
-0.8 
-1.2 
-2.0 



44.3 



40.4 



-3.9 



46.7 



44.6 



-2.1 



46.3 



-2.2 



44.1 



40.7 -3.4 I 45.3 



41.7 1-3.6 



45.0 



42.6 



-2.4 



46.5 



45.3 



-1.2 



1 Estimated; actual readings valueless on account of reflowing or heavy rains. 



Station 2. Sphagnum moss. 
Station 3. Newly sanded, thinly vined. 
Station 4. Newly sanded, heavily vined. 
Station 5. Peat with mos's, heavily vined. 

Highest and lowest readings are in italics. 



Station 6. Old sanded, heavily vined. 
Station 7. Scalped piece, bare peat. 
Station 9. Sandy loam, on upland. 



33 

Table 1. — Minimum Temperatures in Shelter and in open at 5-inch Height, for Each Station, Together 
WITH THE Difference between Readings, Mather, Wis., 1907 — Continued. 



Day of 

month. 



OCTOBER 

1 

2 

3 

4 

5.. 

6 

■ 7 

8 

9 

10 

U 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

Means 



Station 2. 



31.5 

43.3 
39.7 
32.5 
32.7 
38. 6 
41.3 
21.2 
39.0 
28.9 
32.5 
27.5 
21.0 
20.3 
43.4 
34.0 
30. 5 
22.7 
23.0 
26.8 
17.7 
35.4 
26.9 
23.3 
23.5 
18.0 
32.5 
I5.S 
29.3 
36.5 
33.8 



26.6 
4S.1 
35.7 
27.3 
27.0 
33.7 
37.4 
15.9 
32.8 
25.0 
26.0 
22.7 
15.8 
15.6 
39.4 
29.4 
27.4 
17.6 
17.9 
21.9 
13.2 
30.7 
21.9 
17.7 
17.2 
12.5 
29.4 
10.0 
25.7 
34.8 
29.4 



30. 25. 2 



-4.9 
-4.2 
-4.0 
-5.2 
-5.7 
-4.9 
-3.9 
-5.3 
-6.2 
-3.9 
-6.S 
-4.8 
-5.2 
-4.7 
-4.0 
-4.6 
-3.1 
-5.1 
-5.1 
-4.9 
-4.5 
-4.7 
-5.0 
-5.6 
-6.3 
-5.5 
-3.1 
-5.8 
-3.6 
-1.7 
-4.4 



-4.8 



33.0 
SI.S 
43.4 
38.5 
38.3 
42.4 
45.5 
22.7 
38.4 
31.7 
35.0 
29.4 
21.7 
20.4 
43.5 
36.3 
33.4 
24.5 
23.3 
27.3 
18.6 
36.0 
26.6 
24.7 
25.8 
17.6 
34.0 

ie.7 

27.7 
36.7 
34.0 



31.6 



30.0 
46. e 
41.2 
34.0 
35.1 
38.6 
42.7 
19.5 
35.4 
28.4 
31.0 
27.6 
19.5 
17.8 
41.4 
34.3 
30.7 
21.5 
19.6 
24.6 
15.4 
32.3 
23.6 
21.4 
22.4 
14.4 
31.7 
13.5 
23.5 
36.0 
29.3 



-3.0 
-4.6 
-2.2 
-4.5 
-3.2 
-3.8 
-2.8 
-3.2 
-3.0 
-3.3 
-4.0 
-1.8 
-2.2 
-2.6 
-2.1 
-2.0 
-2.7 
-3.0 
-3.7 
-2.7 
-3.2 
-3.7 
-3.0 
-3.3 
-3.4 
-3.2 
-2.3 
-3.2 
-4.2 
-0.7 
-4.7 



28.5 1-3.1 



33.2 

SS.2 
42.7 
36.5 
37.5 
41.5 
44.5 
21.8 
40.0 
31.4 
34.6 
28.8 
21.6 
19.8 
43.6 
35.7 
32.6 
23.6 
22.4 
26.6 
18.4 
35.7 
26.0 
24.7 
25.3 
18.0 
33.7 

le.o 

28.4 
36.8 
35.0 



29.8 
48.8 
40.4 
32.5 
33.7 
38.1 
41.4 
17.7 
34.8 
27.0 
29.7 
20.7 
16.9 
16.8 
42.3 
33.2 
29.4 
20.0 
16.5 
24.7 
13.8 
29.4 
21.0 
19.3 
21.7 
13.1 
31.4 
10.7 
22.3 
36.2 
31.1 



31.2 I 27.4 



-3.4 
-3.4 
-2.3 
-4.0 
-3.8 
-3.4 
-3.1 
-4.1 
-5.2 
-4.4 
-4.9 
-2.1 
-4.7 
-3.0 
-1.3 
-2.5 
-3.2 
-2.6 
-5.9 
-1.9 
-4.6 
-6.3 
-5.0 
-5.4 
-3.6 
-4.9 
-2.3 
-5.3 
-6.1 
-0.6 
-3.9 



-3.8 



Station 5. 



29.5 

es.o 

39.0 
33.3 
34.8 
41.4 
41.6 
18.8 
40.5 
31.4 
30.6 
28.2 
17.5 
16.0 
43.0 
33.5 
31.5 
23.3 
18.4 
26.3 
14.0 
34.3 
23.6 
18.8 
25.0 
13.7 
32.6 
11.0 
29.1 
36.6 
34. S 



29.2 



25.6 
46.7 
35.5 
29.5 
30.3 
35.6 
38.0 
12.8 
34.0 
24.8 
28.3 
25.9 
12.0 
12.4 
41.5 
29.4 
28.4 
20.7 
13.8 
23.5 

9.8 
26.5 
18.8 
14.7 
21.5 

9.3 
31.6 

6.4 
21.7 
35.7 
29.5 



25.0 



-3.9 
-5.3 
-3.5 
-3.8 
-4.5 
-5.8 
-3.6 
-6.0 
-6.5 
-6.6 
-2.3 
-2.3 
-5.5 
-3.6 
-1.5 
-4.1 
-3.1 
-2.6 
-4.6 
-2.8 
-4.2 
-7.8 
-4.8 
-4.1 
-3.5 
-4.4 
-1.0 
-4.6 
-7.4 
-0.9 
-5.0 



-4.2 



Station 6. 



32.0 
5S.5 
41.4 
35.3 
35.1 
43.9 
44.3 
20.1 
40.7 
32.5 
33.4 
28.6 
19.0 
19.5 
43.7 
35.0 
33.7 
22.7 
21.1 
26.6 
17.0 
35.7 
25.7 
21.6 
26.0 
17.5 
33.7 

14. S 

29.6 



26.9 

47. S 

36.8 
29.3 
28.7 
39.0 
39.5 
14.6 
34.9 
26.5 
28.5 
26.2 
13.0 
14.0 
42.0 
32.3 
29.6 
22.5 
15.4 
24.8 
12.5 
28.0 
20.3 
16.0 
22.0 
11.7 
31.6 
8.6 
22.8 
36.3 
28.8 



30.8 



26.1 



-5.1 
-5.0 

-4.6 
-6.0 
-6.4 
-4.9 
-4.8 
-5.5 
-5.S 
-6.0 
-4.9 
-2.4 
-6.0 
-5.5 
-1.7 
-2.7 
-4.1 
-0.2 
-5.7 
-1.8 
-4.5 
-7.7 
-5.4 
-5.6 
-4.0 
-5.8 
-2.1 
-7.7 
-6.8 
-O.S 
-4.5 



-4.7 



Station ; 



31.5 
51.9 
43.2 
35.5 
35.3 
40.6 
42.7 
21.5 
40.0 
31.4 
34.4 
28.6 
20.0 
20.4 
43.0 
34.5 
32. S 
23. S 
21.7 
26.5 
17.3 
34.6 
25.8 
22.4 
26.7 
18.0 
33.4 
14-0 
30.3 
36.5 
35.0 



30.8 



28.5 

4S.0 

38.0 
30.5 
31.7 
37.0 
40.3 
17.5 
37.7 
28.1 
29.5 
26.4 
16.0 
17.0 
41.7 
32.6 
30.8 
22.6 
19.0 
24.5 
14.6 
29.3 
22.7 
19.0 
25.6 
13.7 
31.9 
11.8 
25.8 
36.1 
30.5 



27.7 



-3.0 
-3.9 
-5.2 
-5.0 
-3.6 
-3.6 
-2.4 
-4.0 
-2.3 
-3.3 
-4.9 
-2.2 
-4.0 
-3.4 
-1.3 
-1.9 
-2.0 
-1.2 
-2.7 
-2.0 
-2.7 
-5.S 
-3.1 
-3.4 
-1.1 
-4.3 
-1.5 
-2.2 
-4.5 
-0.4 
-4.5 



-3.1 



.station 9. 



34.0 

51.0 
44.8 
40.0 
40.3 
43.8 
47.3 
22.5 
39.6 
33.0 
34.7 
29.0 
23.0 
21.0 
43.4 
35.8 
3.5. 6 
23.6 
25.5 
27.1 
17.5 
38.3 
28.5 
25.7 
26.5 
16.5 
33.7 
IS. 4 
31.0 
36.6 
35.5 



32.3 



32.3 
SO.O 
43.6 
38.4 
39.0 
41.8 
45.3 
19.8 
37.5 
31.5 
33.7 
28.0 
21.6 
18.9 
42.6 
35.5 
34.2 
23.0 
23.0 
25.8 
15.6 
35.7 
26.6 
23.2 
25.3 
14.8 
33.2 
IS. 6 
29.0 
36.7 
34.3 



30.8 



-1.7 
-2.0 
-1.2 
-1.6 
-1.3 
-2.0 
-2.0 
-S.7 
-2.1 
-1.5 
-1.0 
-1.0 
-1.4 
-2.1 
-0.8 
-0.3 
-1.4 
-0.6 
-2.5 
-1.3 
-1.9 
-2.6 
-1.9 
-2.5 
-1.2 
-1.7 
-0.5 
-1.8 
-2.0 
+0.1 
-1.2 



-1.5 



Station 2. Sphagnum moss. 
Station 3. Newly sanded, thinly vined. 
Station 4. Newly sanded, heavily vined. 
Stations. Peat with moss, heavily vineii. 

Highest and lowest readings are in italics. 



Station 6. Old sanded, heavily vined. 
Station 7. Scalped piece, bare peat. 
Station 9. Sandy loam on upland. 



34 



Table la.— Monthly .\-vd Seasonal Means of Minimum Temperatures in Shelter and in Ope»at .5-inch 
Height, with Difference Between the Readings^ Mather, Wis., 1907. 





May." 


June. 


July. 


Aug. 


Sept. 


Oct. 


Means. !> 


Station 2: 


o 

38.9 
37.2 


45.4 
42.3 


61.8 j 
49.2 


1 

50.1 
47.1 


44.3 
40.4 


30.0 
25.2 


43.4 




40.2 






Difference 


-1.7 


-3.1 


-2.6 


-3.0 


-3.9 


-4.8 


-3.2 


Station 3: 


41.4 
39.3 


48.9 
46.3 


5S.6 
53.0 


53.8 
51.2 


46.7 
44.6 


31.6 
28.5 


46.3 




43.8 








-2.1 


-2.6 


-2.6 


-2.6 


-2.1 


-3.1 


-2.5 






Station 4: 


41.2 
38.8 


48.4 
45.7 


54.9 
52.4 


53.1 
60.6 


46.3 


31.2 


45.8 




44.1 1 27.4 


43.2 






Difference - 


-2.4 


-2.7 


-2.5 


-2.S 


-2.2 -3.8 


-2.B 


Station 6: 

Shelter 


39.7 
37.2 


45.7 
41.8 


53.1 
48.8 


50.3 
47.1 


44.1 ' 29.2 
40. 7 25. 


43.7 




40.1 






Difference 


-2.5 


-3.9 


-4.3 


-3.2 


-3.4 ' -4.2 


-3.6 


Station u: 


40.4 
38.0 


47.0 
43.2 


53.8 
49.6 


52.1 
48.3 


45. 3 30. 8 
41.7 26.1 


44.9 




41.2 








-2.4 


; -3.8 


-4.2 


-3.8 


-3.6 1 -4.7 


-3.7 






Shelter ' 

Exposed 


39.9 
37.6 


46.3 
43.0 


53.0 
50.2 


51.6 
49.0 


45. 30. 8 
42.6 27.7 


44.4 
41.7 




-2.3 


-3.3 


-2.8 


-2.6 


-2.4 -3.1 


-2.7 






Station 9: 


41.2 
40.1 


1 48.4 
46.8 


55.4 
53.8 


53.4 
51.9 


46.5 * 32.3 
45.3 30.8 


40.2 




44. S 








-1.1 


-1.6 


-1.6 


-1.5 


-1.2 


-1.5 


-1.4 







a Means for eighteen days. 

Station 2. Sphagnum moss. 
Station 3. Newly sanded, thinly vined. 
Station 4. Newly sanded, heavily vined. 
Station 5. Peat with moss, heavilj vined 



b Mean difference all stations, —2.8°. 

Station G. Old sanded, heavily vined. 
Station 7. .Scalped piece, bare peat. 
Station ',). Sandy loam on upland. 



35 

Readings of exposed minimum thermometers at the surface and at the 5-incJi. height. — It was 
found impracticable to place thermometers in the shelters at a lower elevation than 5 inches 
above the surface of the ground, and consequently readings of instruments exposed at this 
elevation in the open were used in connection with the discussion of Tables 1 and la. Having 
found the difference prevailing between mmimum thermometers exposed inside and outside of 
shelters, it seemed advisable to determine the difference between the readings of the minimum 
thermometers so exposed in the open and of additional instruments placed at the immediate 
surface. The cranberry vines extend along the surface, their uprights reaching above several 
inches, and readings of instruments placed at different elevations at any particular station 
indicate approximately the temperature which the vmes and leaves experience. Again, the 
temperature at the immediate surface is naturally largely governed by the conditions of the soil 
beneath, and the readings of the surface thermometers were therefore needed in comaection 
with the discussion of soil temperatures. 

It seemed advisable, as far as practicable, to have the tlierniometers at the 5-mch height 
placed directly above the surface instruments, in order that the conditions of the soil and vege- 
tation beneath might be the same for both exposures. This method was followed at all stations 
except Station 4, where, on account of the special conditions prevaihng, it was found necessary 
to place the surface minimum on the ground a few feet distant from tlie instrument exposed at the 
5-inch height. The vegetation over which the surface thermometer was placed at this station 
was more dense than at the point where the upper thermometer was exposed, referred to in the 
discussion of Tables 1 and la. In all cases the lower minimiun thermometers rested upon the 
ground, although at Stations 2 and 9 they were at the same time fastened to the base of the 
post which supported other instruments. Were the conditions exactly the same regarding soil 
and vegetation over a large area at each station, a better comparison would be secured by 
placing the upper instrument at a point sufficiently removed from the surface thermometer so 
that it would not shield in the slightest degree the lower instrument, but it is most difficult to 
secure in a bog surface and soil conditions that are exactly similar for a considerable area. 
There is certain to be a variation in the character and quantity of the vegetation, and some- 
times in the character of the soil, even in a small area. These varying conditions may be also 
considered as factors in the comparison previously made between thermometers exposed in the 
open and in shelters. 

Space does not permit the publication of the daily readings of the two exposed minimums 
at the several stations, but Table 2 shows the montlily and the seasonal averages for the year 
1907. The readings were generally higher at the surface than at the .5-inch height, and espe- 
cialh' so during clear, cool nights. During cloutly and windy weather there was but little differ- 
ence, and sometimes the surface instrument even registered lower. In fact, at the surface at 
Station 4, the average for the entire season was slightly lower at the height of .5 inches, but a 
satisfactory comparison was not possible at that point, for reasons given above. 

There was also a complication at Station 7, in that these thermometers were placed in the 
middle of a scalped piece, 10 feet square, surrounded l)y a section of dense sphagnum moss. 
As stated in a previous paragraph, the instruments were exposed usually over a surface that was 
representative of a large section of the bog surrounding it, because the temperature naturally 
is affected by the surface conditions, not only at the point of exposure, but for a considerable 
area in the vicinity. However, at Station 7 the scalped area was only a relatively small section 
within an extensive field of sphagnum moss. Moreover, the soil at this station during 1907 
was very damp, and the consequent evaporation affected the surface thermometer more than 
the one at 5 inches. 

The depression of the thermometers at the .5-inch height was greatest during cold, clear 
nights, with comparatively high barometer and light wind, when radiation was freest, appar- 
ently for the same reason that the exposed minimums registered lower than those in shelters. 
(Table 1.) The moisture resulting from dew, ram, or reflowing sometimes affected the readings 
of the instruments, especially when water covered the bulbs of the thermometers. For instance, 
dew occasionally formeil on the bulb of the upper thermometer when the lower was perfectly 



36 

dry, and at other times the lower thermometer remained wet from rain, the cold of evaporation 
sometimes lowering the readings of the instrument, especially when rain was followed in the 
nighttime by wmd. At such times the upper thermometers were usuaUj" higher than the 
lower ones — an inversion of the usual conditions. Often this difference amounted to several 
degrees. On the other hand, water fi-om a warm rain remaining on the bulb of a thermometer 
often sei-ved to raise its reading when the air remained humitl and calm. 

There seemed to be no uniformity in the variation from month to month, although usually 
the differences were greatest in October. The average depression of temperature at the 5-inch 
height beloAv that at the surface for the season of 1907 was 1°. The average depression on clear, 
cool nights probably reached 4°. There were several instajices of differences exceeding 6°. The 
greatest average monthly depression of the upper thermometers for any one month was 3°, at 
Station 5, in October. At Station 4 the lower thermometer averaged 0.4°, 0.5°, and 0.1° lower 
in May, June, and July, respectively, than the upper thermometer. However, in September and 
October, at Station 4, '^"' lower minimum averaged, higher than the u])per one hy 0.1° and 0.2°, 
respectively, and in August there was no difference. The lack in uniformity of the vegetation at 
Station 4 has been referred to above. 

In the year 1906 similar data were available for Stations 3, 5, 6, 7, and 9 for the months 
of August and September. The average depressions of the thermometers at the 5-inch height 
below those at the surface for the month of August in the years, 1906 and 1907, respectively, 
were as follows: Station 3, 3° and 2.5°; Station 5, 1.6° and 1.7°; Station 6, 1.2° and 1°; Station 
7, 3° and 0.2°; Station 9, 0.6° and 0.7°; for the month of September, 1906 and 1907: Station 3,. 
4.7° and 1.3°; Station 5, 2.4° and 2.3°; Station 6, 1.6° and 1.4°; Station 7, 4.8° and -f 0.3°«; 
Station 9, 1° and 0.3°. 

It is not easy to state the exact reasons for these great differences m temperature. Of 
course, the upper thermometers were so placed that there was freer radiation from them than 
fi-om those at the surface; yet it is not thought that thi- difference in radiation should be sufficient 
reason for such great differences in temperature, reaching a maximum difference of 6° and even 
7° on several nights. The fact that the thermometer exposed at the surface at Station 4 aver- 
aged lower during more than half the season than the one at the 5-inch height, and that at that 
station the thermometers were [)laced several feet apart, and not one directly above the other, 
as at other stations, might suggest that at the remaining stations the surface thermometers 
generally registered higher because they were shielded by the thermometers immediately above. 
It is, however, difficult to believe that the very slight interjjosition of the upper thermometer 
could be responsible for differences of several degrees, as often occurred. The fact that the 
surface thermometer at Station 4 was located on a surface more densely covered with vegetation 
than the place where the uj)j)er thermometer at the same station was located should partially 
account for the apparent inconsistency in the readings at that station. There was so much 
water at Station 7 in 1907 as compared with 1906 as to seriously affect the comparison of the 
thermometer readings, and it is because of the great amoimt of evaporation in 1907 at the 
surface that the lower minimum averaged relatively" lower than in 1906. 

In a marsh grasses and uprights from the vines interfere slightly with radiation fi-om the 
thermometers placed on the surface, and it is probable that a thermometer or leaf exposed at an 
elevation above the surface loses its heat more rapidly by radiation than if it rested upon the 
surface, because the upper one is not shielded in any way, and while the radiation is going on 
from the lower one, at the same time heat is being conducted to it from the ground beneath. 
A thermometer resting upon the surface of the bog becomes a part of the soil or vegetation upon 
which it rests, as it were, and is benefited by the free conduction of heat to it from the ground, 
while .the conduction to and tlu-ough the air is very slight in comparison; because of these differ- 
ences in radiation and conduction, the surface thermometer usuaUy registers a higher tempera- 
ture than the instrument a few inches above. For the same reason, the temperature of the 
vegetation at the surface and 5 inches above wouhl var}' as these temperatures have varied, 

1 Surface instrument registered lower. 



37 



especially when the surface vegetation is shielded by vegetation above. It is a matter of 
common knowledge that in the bogs the cranberries growmg at the tops of the uprights a few 
inches above the ground are often damaged by frost, while those lying on or near the ground 

escape injury. ^ ,-„. i. i i- -n 

The readings of exposed mininuini thermometers at a number of different elevations wiU 
be discussed in detail later in connection with Tables 13 and 14, in order to show approximately 
the height above the ground at which the lowest minimum occurs. 

Table 2.-Monthly and Seasonal Means of Minimum Temper.'^.tuees in open at Surface and at 5-inch 
Height, with Difference Between the Readings, Mather, Wis., 1907. 





May." 


June. 


July. 


Aug. 


Sept. 


Oct. 


Means, b 


Station 2: 

Surface 

5 inch 


37.6 
37.2 


43.3 
42.3 




52.0 
49.2 


49.4 
47.1 


41.9 
40.4 


27,5 
25. 2 j 


41.9 
40.2 


Difference 


-0.4 


-1.0 


-2.8 


-2.3 


-1.5 


-2.3 -1.7 


Station 3: 


40.4 48.8 
39.3 ■ 46.3 


55.5 
53.0 


53.7 
51.2 


45.9 
44.6 


28.8 


45.5 


5 inch 


28.5 


43.8 


Difference. . . 


-1.1 j -2.5 


-2.5 


-2.5 


-1.3 


-0.3 


-1.7 


Station 4: 


:!S. 4 45. 2 
38.8 , 45.7 


52.3 
62.4 


50.6 
50.6 


44.2 
44.1 


27.6 
27.4 


43.1 


5 incti 


43.2 


Difference 


+0.4] +0.5 


+0.1 


0.0 


-0.1 


-0.2 


+0.1 


station 5: 


:C A 43.5 
37.2 41.' 8 


49.8 
48.8 


48.8 
47.1 


43.0 
40.7 


28.0 
25.0 


41.7 


5 inch 


40.1 


Difference 


+0.1 1 -1.7 


-1.0 


-1.7 


-2.3 


-3.0 


-1.6 


Station 6: 


38. 7 44. 
38.0 1 43.2 


50.3 
49.6 


49.3 
48.3 


43.1 
41.7 


28.3 
26.3 


42.3 


5 inch 


41.2 


Difference 


-0.7 -0.8 


-0.7 


-1.0 


-1.4 


-2.0 -1.1 


Station 1 : 

Surface 

5 inch 


37. fi 44. 
37.6 43.0 


51.2 
50.2 


49.2 
49.0 


42.3 
42.6 


27.9 
27.7 


42.0 
41.7 


Difference 


0.0 -1.0 


-1.0 


-0.2 


.+0.3 


-0.2 1 -0.3 


Station 9: 

Svirface 

5 inch 


' 40.9 1 48.7 
40.1 46.8 


55.0 
53.8 


52.6 
51.9 


45.6 
45.3 


31.1 
30.8 


45.6 
44.8 




-0.8 -1.9 


-1.2 


-0.7 


-0.3 


-0.3 ' -0.8 










' 



o Means for eighteen days, 
station 2. Sphagn\im moss, 
station 3. Newly sanded, thinly vined. 
station 4. Newly sanded, heavily vined. 
Station 5. Peat with moss, heavily vined. 



b Mean difference all stations, 1.0°. 
Station 6. Old sanded, heavily vined. 
Station 7. Scalped piece, bare peat. 
Station 9. Sandy loam on upland. 



Ohservations of temperatures in soil and at the surface in different locations, 3Ia the r, Wis., 

1906 and 190?.— This discussion has already shown that there is a wide difference in temperature 
at various points at the surface and a few inches above, in the same bog, and that the vegetation 
in ])ottom lands is subjected to temperatures of varymg degree. It seemed desirable to deter- 
mine what relation, if any. exists between the temperature at and near the surface and the 
character of the soil and its covering. Observations made at Mather, Wis., durmg 1906 and 

1907 of soil temperatures in connection with exposed thermometers above the surface furnish 
interesting data bearing on this subject . The average readings are herewith given for September, 



38 

1906, for four selected stations, this being preliminary to the more extensive obsew^ations of 

the following year. ' 

Average Temperatures for September, 1906, Mather, Wis. 



Maximum soil temperature, 3 inches- 
Minimum soil temperature, 3 inches. 

Nightly loss of soil heat, 3 inches 

Exposed minimum at surface 



Station 3. 


Station 4. 


Station li. 


. 


„ 


. 


64.2 


ti3.2 


(il.l 


.if.. 1 


.59.1 


39.1 


8.1 


4.1 


2.0 


51.2 

1 


47.9 


44.2 



Station .5. 



59.8 
59.2 



Station 3. newly sanded and thinly vlned, representing best conditions of sanding, draining, and cultivating, 
station 4. newly sanded and heavily vined, representing best conditions of sanding and draining. 
Station G. old (9 years), sanded and heavily vined, stratum of peat, 1 inch in thickness, over old sand. 
Station 5, uncultivated marsh, peat, and sphagnum moss, poorly drained. 

The soil thermometers were placed at a deptli of 3 incites, and it was found by a series of 
eye observations and by comparison with the soil thermograph traces that the maximum soil 
temperatures usually occurred at about 6 p. m. and the minimum soil tem])eratures at about 
7 a. m. (See Fig. 20, showing average hourly soil thermograph reatlmgs at Stations 3 and 
5, Mather, Wis., 1907.) The above table shows that the highest maximum soil temperatures 
and the lowest minimum soil temperatures at the depth of 3 inches and the highest exposed 
minimums occurred in the sanded sections, bare or thinly vined and well dramed, while the lowest 
maximum soil temperatures, the highest minimum soil temperatures, and the lowest exposed 
minimums were founil in the uncultivated marsh, which was poorly drained and had a thick 
growth of vegetation and sphagnum moss. 

Prof. W. J. Humphreys" says: ''The better the absorber, other things being eciual, the 
warmer it gets during insolation and the more it heats the air, while the better the radiator it 
is, thte colder, as a rule, it and the air adjacent become during the night. When the atmosphere 
is clear and tlry, and therefore diatheimanous, the cooling of objects and their liability to fi'ost 
depends largely upon their capacity to radiate at ordmary temperatures. A good radiator 
under these conditions loses heat partly by radiation through the atmosphere to space. It 
cools rapidly, but the heat it gives off does not all go to wanning the air, for, as ex]ilained, a 
part of it is directh' lost to space. On the other hantl, an t)bject that radiates poorly gives 
off heat slowly, and what it tloes give off is in a large measure by conduction to the atmosphere. 
It tentls to conserve both its own temperature and that of the surrounding air, and thereby 
diminishes the probability of frost." 

As stated before, during the day the surface of any solid upon which the sun shmes becomes 
hotter than the air above it. A thermometer resting upon the ground becomes a part of the 
soil or vegetation, as it were, and the readmgs of the instrument indicate relatively high or 
low maximum temperatures in the daytime and relatively high or low minimum temperatures 
at night, de])ending upon the radiation, absorption, and conduction of heat under the various 
existing <'onditions. The vegetation as found in the bogs is an excellent radiator and absorbs 
well, but of ('ourse conducts and transmits heat to the soil very slowly. The heat lost from 
vegetation is largely by radiation tlirough the air without heating it sensibly. Peat soil is 
also a good absorber and radiator, but it is a poor conductor; but the heat received at the 
surface is partly conducted into the peat. The sanded surface is not as gooil an absoi'ber, but 
it is a much better conductor of heat. The heat, moreover, of the sand in the j)iesence of air 
is lost lai'gely by conduction to it, and conse([uently serves to heat tiie air lyhig immediately 
above — in strong contrast to the conditions over a heavily vined surface or plain peat, where 
the loss is mainly by radiation. 

A knowledge of these facts is important in connection with the more extensive observations 
made at Mather during the season of 1907, readings of exposed maximums antl of exposed 



" Bulletin of the Mount Weather Observator)', Vol. II, pt. 3. 



39 

minimums being; made as well as of soil temperature. The Stations 3, 4, 5, and 6 selected are 
fairly representative of the conditions prevailing in a cranberry bog. Only the summary of 
the conditions for 1907, inchuling maximum and minimum averages, appears in Table 3. There 
is not sufficient space for the daily readings. Four stations, as in the previous year, are suffi- 
cient for this comparison, and an additional number would merely repeat the results here 
furnished. The readings of the maxinnim and the minimum thermometers are from instru- 
ments exposed in the open at the surface. The soil thermometers at the various stations were 
placed at a depth of 3 inches in the vicinity of the surface thermometers. For purposes of this 
discussion it would have been better if the bulbs could have been placed just beneath the sur- 
face. But in a bog it is rather difficult to determine where the actual surface begins, as it is 
generally covered with vines, grasses, leaves, and decaying vegetation, gradually turning to 
peat. '^Vliere the vegetation is dense, the effective surface is actually above the surface of the 
soil. The sanded surfaces differ radicall}^ from the surfaces that are not sanded. On account 
of these circumstances and because of the difficulty of maintaining the soil thermometers in an 
upright position, except at a moderate depth, so as to firmly secure them, no attempt was made 
to obtain readings of the soil temperature at a depth less than 3 inches. In the original tables, 
of winch Table 3 is the summary, the readings of the soil thermometers which were made at 
6 p. m. are entered under the succeeding date, and the differences between these readings and 
the following 7 a. m. readings show the nightly loss or range in soil temperature. 

The difficulty in an investigation of this kind is to maintain uniform conditions at the 
various stations, so that data may be fairly comparable at all times iluring tlie season, i)ut this 
is quite impossible, as the vegetation is likely to remain uniform at one station, while at other 
stations it may either increase or decrease in density. During the season of 1907 the conditions 
at Stations 3 and 4 changed but little, the surface at Station 3 being relatively clean, wliile at 
Station 4 the vegetation remametl dense. The vines at Station 5 were dymg out after mid- 
summer to such a degree as to seriously affect the readings of the instruments. In fact, twice 
during the month of August a change in the location of the soil instruments was made in order 
to counteract the changuig conditions. The density of the vegetation at Station 6 steadily 
decreased as the end of the season approached, but there was no change in the location of the 
uistruments as at Station .5. If the cranberry vine were a bush, as some jjcople believe, theie 
would not be much difficulty in maintaining uniform conditions of foliage, but it is a vine 
spreading in all directions fiom the crowii, so that constant trampling at one place often affects 
the condition of the vegetation several feet distant. 

There is, for the reasons given above, a greater uniformity in the readings at Stations 3 
and 4 than at the other stations. At Station 3 for the entire season the exposed maximums 
averaged the lowest and the exposed minimums and the 6 p. m. soil temperatures the highest, 
although the 7 a. m. soil temperatures averagetl the lowest. At Station 5 the exposed maxi- 
mums averaged the highest from May to August, inclusive, but in September the maximum 
at Station 4 was slightly higher and in October much higher than at Station 5. The lack in 
uniformity was undoubtedly caused by the steady change in vegetation at Station 5, as referred 
to above. This change at Station 5 is also apparent in the comparison of the minimums at 
Stations 4 and .5, the average minimum in October at Station 4 actually being lower by 0.4° 
than at Station .5, while in the other months it was considerably higher. The persistency of 
the dense vegetation at Station 4 until the end of the season is quite apparent from the read- 
ings of the instruments, especially in October. It was at Station 4 that the surface minimum 
averaged lower than at the 5-inch height, as referred to in the discussion of Table 2. On account 
of the enforced change of the soil instruments at Station 5 in August, these readings are not 
strictly comparable in September and October with the soil data at the other stations. 

At Stations 4, 5, and 6 the soil was so shielded from the sun's rays as to prevent its warm- 
ing to any great degree, much of the absorbed energy being used to produce plant growth and 
evaporation, and consequently the loss or range of heat was small as compared with that at 
Station 3. The difference in range of soil temperature at the 3-inch depth at certain stations, 



40 



caused b}^ variation in soil and covering, at Mather, Wis., is graphically shown. in figure 19; 
also in Figure 20, which shows the average hourly soil temperature at depths of 3 and 6 inches 
at, Stations 3 and 5. 

"While the 7 a. m. or mininiiini soil temperature readings at the depth of 3 inches at Station 
3 averaged lower than at the otlier stations, it is probable that the minimum temperature of 
the soil at the immediate surface at Station 3 averaged higher than at tlie other locations, 
because the exposed minimum temperature was higher. As the exposetl maximum tempera- 
ture at the various stations was affectetl by the vegetation, so also was the exposed minimum, 



i^, ,^iy.. 4 i - 


'^/.■. 


< . ~,W/ , i < 


■■\f: , f . -mi. , 


-■:J/-/-:1/-"/- 


..yt: , / , ..j-j'.' ^ < . • (/■• ' ■ ■ r ■■ > • V, 


^t=f 23 




21 


■jr, 


'jG 


! ■ ! : 27 /;//-; ^v — 


^--■' 












z . -. i : L t - ■ ; 


:.: . ^—1^-+^^ .-: 



"llTTTTTJTTT 

'•i'~ ^' ' ' ' ' J30 



r- .631- -^- 




(*> ■ ^ — ■■ ■ - - 

Fig. 19.— Soil temperature curves at three inch depth for Stations 3, 4, and 5. Mather, Wis., September 23 to 30, 1906. Station No. 3, soil 
temperature in bog newly sanded, thinly vined, 3 inches deep : station No. b. soil temperature in peat bog with moss 3 inches deep 

- - - - . : station No. 4. soil temperature in bog newly sanded, heavily vined, 3 inches deep — x — x — x — x— x — . 

the lowest miuimums prevailing generally at the stations where the maximums were tiie 
highest. Obviously the uicreasing vegetation, serving to raise the exposed maximum in the 
daytime, was also responsible for the great radiation at night, especially during clear weather, 
and as a consecjuence the miniinums were lowest wliere the vegetation was densest and highest 
where it was thimiest. "Wliile the loss of heat at night from the vegetation is largely by radia- 
tion and through the air without warming it, at places where the surface was sanded the loss 
of heat was partly by conduction to tiie air above. .Although the vegetation was dense at 
Station 4, the surface had been recently sanded, and the surface at Station 6 had been sanded 

in 1898. Tlie influence of this sand- 
ing at wStation 4 and even at Sta- 
tion 6 is apparent in the readings 
of the maximum soil tempera- 
ture, the range in soil temperature, 
ami the exposed minimum tem- 
perature, as compared with similar 
readings at Station 5, although a 
layer of peat an inch in thickness 
had formed over the sand at Sta- 
tion 6. The vegetation at all thi-ee 
stations was ilense and prevented 
great heating of the soil, but nev- 
ertheless the sand, being a better 
conductor of heat than the peat. 

Fig. 20.— (1) Traces showing average hourly soil temperature for the .season of 1907 brought a trreater SUPplv of llCat 

at a depth of 3 inches and (1 inches. Station 3. Mather, Wis. (3 inches _^^. . ^ , -T i' . . 

6 inches .) (2) Traces showing average hourly soil tempera- l^to the SOU, tllUS Conserving it to 

tures for the season of 1907 at depths of 3 inches and 6 inches. Station 5, Mather, be "iven off later at uio'ht bv Con- 
Wis. (3 inches 6 inches .) "^ . , . . '' -^ ' 

duction and radiation. The sand, 
then, was probably as much responsible as the better drainage for the higher exposed mhii- 
mum temperatures at Stations 4 and 6, as compared with Station 5, the drainage at both 
Stations 5 and 6 being relatively poor, resulting in a consideraldo loss of heat through evap- 
oration of the moisture at the surface. The conditions at Station 6 resembled those at Stations 
4 and 5 equally, because although the vegetation at Station 6 was dense until after midsum- 
mer, it graduallv died away, and for this reason the exposed maximums averaged during 
October even lower than tho.se at Station 3. 




-1:1 

These observations in 1907 confii'm those of 1906 in that the highest maximum soil tem- 
peratures and the lowest minimum soil temperatures at the depth of 3 inches, the greatest 
range in soil temperature, and the highest exposed minimums occurred in the thinly vined, 
well drained, and sanded sections, wliile the lowest maximum soil temperatures and highest 
minimum soil temperatures, the least range m soil temperature, and the lowest exposed mini- 
mums were found in the uncultivated marsh, which was poorly drained and heavily vined. 
Moreover, the highest average exposed maximums occurred where the vegetation was dense, 
while the lowest average maximums occuned in tlie sanded and tlunly vined section. Other 
things being equal, the higher the maximum temperature on any one day the higher was the 
maximum soil temperature at the depth of 3 inches and the ensuing exposed minimum tem- 
perature. Again, other things being equal, the higher the maximum soil temperature on any 
one day the higher was the ensuing exposed minimum temperature. In other words, there 
was a close relation between the daily maximum air temperature and the soil temperature and 
a close relation between the soil temperature and the ensuing exposed minimum temperature. 
It is for this rea.son that in the spring and fall, when the ground is cold, frost occurs in the bogs 
much more eivsily than in the summer, when the soil is warm. 

The high exposed minimums at Station 3, as compared with those at the other stations, 
are ((uite remarkable, and the advantages from cultivation, draining, and sanding are well 
illustrated. The difference between the minimum temperatures at Station 3 and at the other 
stations is least in October, ami this is probably because frost had entered the surface of the 
soil. WTiereas sand during the crop season is most valuable in warding off low night tem- 
peratures, it is probable that after frost has once entered the soil its character is not of much 
consequence, ^\^lile the exposed maximums on cloudy daj^s varied little at the different sta- 
tions and did not reach a high degree, the minimum temperatures on cloudy nights differed 
little and were relatively Irigh. There was, moreover, but little difference between the mini- 
mums on windy nights. At no station during the season did the temperature of the soil at 
the tlepth of 3 inches fall to the freezing point, the lowest reading being 33.8° on the morning 
of October 2S at Station 3. On the same day the readings at the other stations were as follows: 
Station 4, 37.1°; Station 5, 40.3°; and at Station 6, 37°; but at all stations on the bog the 
ground at the immediate surface was frozen. 

The range in the exposed minimum temperature at the surface of a bog, as sho-WTi by 
Tables 2 and 3, does not, of course, actually represent the extremes, the exposed minimums at 
the 5-inch height as a rule registering lower than those at the surface. In later tables embody- 
ing the daily readings of the exposed minimums, both at the surface and 5 inches and then- 
respective differences, will be showm in detail the extreme differences at the coldest and the 
warmest places on the bogs. 

The highest exposed maximums were reached about July 20, the greatest being 128.1° 
on that date at Station .5. On the same date the exposed maximum at Station 3 was 110°; 
at Station 4, 121.7° ; and at Station 6, 120°. The soil temperature readings at 6 p. m. at Stations 
4, 5, and 6, reached their maximum from four to five days later, there being an irregular increase 
from the beginning of the season in May to the summer maximum, and, in turn, a decrease 
from the maximum to the minimum near the end of October. The highest soil temperatures 
at the various stations in July were as follows: Station 3, 76.3° on the 20th; Station 4, 69.7° 
on the 24th; Station 5, 71° on the 25th; and Station 6, 71.5° on the 24th. The maximum 
of the season, however, at Station 3, in the tliinly vined and sanded section, was not reached 
until August 31, when a temperature of 78° was registered. The exposed maximums at Station 
3 seldom registered higher than 110°, but at Stations 4, 5, and 6, where the vegetation was 
dense, the readings frequently exceeded 120°. The greatest daily range between the exposed 
maximum and the exposed minimum at any one station was at Station 5, 89.9°, on July 2, 
from a maxmmm of 119.9° to a minunum of 30°. The daily range in exposed temperature 
was seldom less than 20°, except at Station 3. At that station there were a few instances of 
ranges less than 10° in October, and one or two others during the balance of the season. 



42 

There is, of course, a direct relation between the air temperature and the soil temperature, 
an increase of heat during tlie day serving to raise tlie temperature of tlie soil; and this, in 
turn, prevents low minimum temperatures at night. Where the air temperature was low in 
the daytime, and, as a result, the soil remained cold, low minimum air temperatures were sure 
to follow, provided the weather at night was clear, so as to permit free radiation of heat. 
While usually there was a loss of heat from the soil at night, occasionally the temperature of 
the soil rose. On October 2, during a cloudy, warm night, following a cold day, the tempera- 
ture of the soil rose at the various stations, the increase reaching a maximum of 1.7° at Station 
6. On certain cloudy, warm nights there was a slight rise in the soil temperature at Stations 4, 
5, and 6, while a fall occurred at Station 3. The greatest nightly loss in soil temperature was 
at Station 3, 17.8° on October 18, from a maximum of 57° to a minimum of 39.2°, while at the 
other stations the nightly loss in soil temperature seldom exceeded 5°. The range in soil 
temperature is a measure of the heat absorbed during the day and lost at night by the soil, and 
responils from day to day to changes in insolation. 

The amount of heat received in the daytime by the soil at the different locations is shown 
in a measure by the 6 p. m. soil-temperature readings. At the 3-inch depth the average for the 
season of 1907 at Station 3 was 62.6°, as compared with 58° at Station 4, 56.6° at Station 5, 
and 57.2° at Station 6. (Tables 3 and 19.) Moreover, at the 6-inch depth, the average soil- 
temperature readings were as follows: Station 3, 59.8°; Station 4, 56.2°; Station 5, 55.2°; 
Station 6, 55.6°. These figures not only show that the temperature of the soil near the sur- 
face in the thinly vined and sanded section is usually much higher than in the other sections, 
but also that the heat reaches to a greater depth. In this connection, see Figure 20, showing 
the soil-temperature curves at both 3 and 6 inches at Stations 3 and 5 for the season of 1907. 
The range in temperature of the soil immediately beneath the surface is untloubtedly greater 
than at the depth of 3 inches. It should be evident that where the soil temperatures are high, 
more heat may be lost by conduction and radiation from the soil before the point of critical 
air temperature at or immediatelj' above the surface is reached, even if the loss by radiation 
tlirough the air be at the same rate at all locations. However, the radiation from a peat bog 
with a heavily vined surface is much freer than where the surface has been sanded antl is thinly 
Arined, the loss of heat from the latter j)robably being largely by conduction to the air, and there- 
fore slower. The sanded and thinly vined surface conserves the heat, not only in the soil, 
but also in the air immediately above, while a dense growth of vegetation prevents the soil 
beneath from being heated considerably in the daytime. The degree to which the temperature 
falls during the night depends largely upon the warmth of the soil, and when the heating 
during the day has been slight, and the ensuing night is clear, thus permitting rapid radiation, 
low minimum air temperatures must result, as stated above. 

It is apparent from tills discussion that the air temperature is controlled largely by the 
character of the soil and its covering. Such a remarkable variation as is here shown explains 
why frost may visit one portion of a bog, while another portion may escape injury. On any 
clear, cool night the cold air, as it settles gradually through gravity, overspreads the bog, and 
here and there are found warm places and cold places and others having an intermediate 
value, depending upon the character of the soil and its covering. It is as if heaters of varying 
power were scattered over the bog, giving off heat to the air immediately above, some in greater 
quantities and others in less. The difference in temperature of a surface covering is some- 
times apparent when the first light snow falls in the autunm or early winter, before the ground 
becomes cold, the snow melting where the ground is bare of growth, but remaining where the 
vegetation is dense. Likewise, under similar conditions, snow melts when it falls upon a 
concrete walk, though remaining on a board walk; and the first frost of the .season is always 
seen on the latter. The heat stored in the bare soil and in the concrete walk is conducted 
to the surface, and affects the temperature at the surface as does a sanded and thinly vined 
soil in the bogs. Figures 21 and 22 will supplement Table 3. 



43 



Table 3. — Monthly and Seasonal Mean.s of Ma.ximum and Minimum Temperatures at Surface in Open, with 
Range; also Means of Soil Temperatures, 3-inch Depth, and of Loss during the Nioht, Mather, Wis., 

1907. 

[The G p. m. soil temperatures occurred the previous day.] 





May." 


June. 


July. 


Aug. 


Sept. 


Oct. 


Means. 


Station 3: 
Surface— 


79.5 
40.2 


95.7 
48.8 


99.6 
55.5 


89.9 
53.7 


80.9 
.45.9 




62.1 
28.8 


84.6 












39.3 


46.9 


44.1 


36.2 


35.0 


33.3 


39 1 






Soil, 3 inch— 


56.3 
48.0 


65.9 
56.9 


71.8 
63.1 


68.6 
61.4 


63.2 
55.3 


49.6 
41.9 

-7.7 


62.6 




54 4 






Loss 


-8.3 


-9.0 


-8.7 


-7.2 


-7.9 


-8.2 






Station ■!: 
Surface— 


84.5 
38.2 


103.4 
45.2 


110.1 
52.3 


99.4 
50.6 


85.4 
44.2 


72. 7 
27.5 


92.6 












46.3 


58.2 


57.8 


48.8 


41.2 


45.2 


49.6 






Soil. 3 inch- 


50.5 
47.6 


60.2 
56.5 


66.9 
63.2 


64.6 
61.5 


59.3 
56.5 


46.6 
44.0 


58.0 




64.9 








-2.9 


-3.7 


-3.7 


-3.1 


-2.8 


-2.6 


-3.1 






Station 5: 
Surface- 


84.7 
36.8 


104.4 
43.5 


112.2 
49.8 


101.3 
48.8 


85.0 
43.0 


64.7 
27.9 


92 fl 


Minimum. 


41.7 






Range 


47.9 


60.9 


62.4 


52.5 


42.0 


38.8 


50.3 


Soil, 3 inch— 


48.6 
47.6 


57.9 
55.6 


66.2 
63.6 


64.0 
62.1 


57.2 
56.5 


45.9 
45.5 


56.6 


7 a. m 


55. 1 






Loss 


-1.0 


-2.3 


-2.6 


-1.9 


-0.7 


-0.4 


-1.5 






Station ti; 

Maximum .... . 


80.1 
38.6 


99.8 
44.0 


105.9 
50.3 


97.1 
49.3 


81.4 
43.1 


6I«1 
28.3 


87.4 




42.3 








41.5 


55.8 


55.6 


47.8 


38.3 


3L8 


45.1 






Soil, 3 inch— 

6 p. m 


49.5 
47.3 


59.1 
56.3 


65.9 
63.4 


63.6 
61.4 


58.5 
56.3 


46.6 
44.6 


57.2 
64.9 




-2.2 


-2.8 


-2.5 


-2.2 


-2.2 


-2.0 


—2.3 







1 Means for sixteen days. 



Station 3. Newly sanded, thinly vined. 
Station 4. Newly sanded, heavily vined. 



Station 5. Peat with moss, heavily vined. 
Station G. Old sanded, heavily viupd. 



Air temperatures and soil temperatures at Station 7 and Station 7a, Mather, Wis., September, 
1906. — The facts brought out by the comparative data appearing in Table 3 are accentuated 
by obsers^ations made in 1906 at Station 7, and at a supplementary station, 7a, which show 
how much the minimum temperature at an elevation above the surface depends upon the 
environment. When the investigation was commenced in 1906 at Mather it seemed desirable 
to have one station located in a section of plain peat, absolutely free from vegetation. No 
such section was available, nor was it practicable to scalp a portion of the cranberry marsh 
proper for the purpose. An area, however, 10 feet square, in the midst of an extensive field 
of sphagnum moss, immediately outside, was cleaned up. Thermometers were placed in the 



44 

center of the scalped piece, Station 7, and 5 or 6 feet distant over the moss, Station«f«, near 
the edge. Station 7a was not continued in 1907, and as Station 7 itself was under water for a 
considerable portion of the same year, data for 1907 at that Station are not as serviceable 
as they otherwise might be. Data for September, 1906 (Table 4), furnish some interesting 
results. The average exposed minimum at the surface of Station 7 was much higher than at 
the surface at Station 7a, there being a difference of 5.6°. On every day the minimum was 
higher at the surface of Station 7 than at the surface at Station 7a, with but a single exception, 
and a maximum difference of 11° occurred on September 25 — a remarkable variation in tem- 
perature within a distance of 5 or 6 feet. Tliis is because, in a soil covereil with a thick layer 
of moss, the opportunity for conduction down is not good, and much of the absorbed solar 
energy is used in proilucing plant growth. Thus the moss-covered soil does not store up as much 
sensible heat as does the bare soil, although the moss and the bare peat are equally good radiators. 

The difference between the average minimums for the month at an elevation of 5 inches, 
however, was only 0.5°, Station 7 still reading higher on the average, although there were 
several instances where it was lower. The minimum, at the 5-inch height at Station 7 averaged 
4-8° lower than at the surface, while at Station 7a the temperature at 5 inches aimraged 0.3° higher 
than at the surface. This inversion of the usual conditions at Station 7a was doubtless caused by 
the warmth from the area of bare soil adjoining. In other words, the temperature at the 
5-inch height over the bare peat at Station 7 was affected by the surrounding area of sphagnum 
moss, and consequently lowered, while the temperature over the adjoining moss at Station 7a 
was affected in the other direction, but in a lesser tlegree, by the small area of bare peat imme- 
diately adjoining. There was probably a slow circulation of air at night between the moss 
and the bare soil. These results indicate quite plainly that while the temperature at the 
surface depends upon the character of the soil and vegetation at the point of exposure, the 
temperature a few inches above is affected not only by the character of tliis vegetation and 
the soil immediately beneath, but by the environment as well. If the scalped piece were 
greater in extent, 40 or 50 feet square or more, the thermometers exposed in the center of the 
area 5 inches above the ground would probabh^ not be considerably affected by the surrounding 
moss. The thermometer on the moss, however, near the edge of tliis larger scalped piece, 
would, on the other hand, be affected even more than in the case of the small 10-foot area 
used in this investigation. 

Table 4, under the soil-temperature column, at the .3-inch depth, illustrates the great 
range in temperature of the clean soil as compared witli that covered with a dense growth. 
The avejage 6 p. m. i-eading at Station 7 was 65.8°, as compared with 61.3° at Station 7«. 
The maximum soil temperature was 73° at Station 7 on September 12, wliile it was only 63.8° 
at Station 7a on the same day. The average loss of heat during the night at Station 7 was 
6.1°, as compared with 0.2° at Station 7a, while the minimum, or 7 a. m. soil reachngs, averaged 
lower at Station 7 than at Station 7a, at the 3-inch depth. The greatest loss in soil tempera- 
ture at both stations was on September 14, 11.2° at Station 7, and only 1.2° at Station 7a. 
On September 16, during a warm, rainy night, following a cool day, the soil temperature at 
Station 7 actualh' rose 0.5°, while at Station 7a the rise was 0.6°. On the night of September 
2 the soil temperature at Station 7 rose 0.2°, wliile at Station 7a the rise was 0.4°. These 
were the only instances where the temperature rose in the nighttime at Station 7, but there 
were a number of instances where the temperature rose at Station 7a, its soil being so protected 
from the sun's rays that the change in temperature was not only small, but lagged behind that 
at Station 7. The moss loses its heat rapidly and receives heat from below but slowly, partl}'^ 
because the supply there is not great and partly because the connection, being mainly through 
the stems, is not such as to give good conduction. On the other hand, the bare peat soil has 
a good supply of heat to draw upon and has direct connection Avith the atmosphere above. 

\¥lnle the minunum temperature at the depth of 3 inches was lower in the bare section 
than in the moss, it is quite certain that at the immediate surface the temperature in the bare 
soil was higher. It is apparent that the bare soil conserves the heat, while a soil covered with 
a dense growth, such as moss, is heated but little by the sun's rays, an exposed minimum there- 



45 



fore at the immediate surface of the clean section registering much higlier than over the moss. 
The varying temperature of tlie ground is furtlier evidenced l)y tlie habits of cattle in pasture. 
On warm summer nights they lie down where the ground is covered with grass, so as to be 
cool, while on cool, clear nights they seek the warmer bare soil. 

Table 4. — Minimum Temperatures in Open at Surface and 5-Inch Height, Together with Differences: also 
Soil Temperature Readings Showing Loss during Night, Mather, Wis., September, 1906. 

[The 6 p. m. soil readings are those which occurred the previous day.] 





Station 7 (over bare peat). 


Station 7a (over sphagnum moss). 


Day of month. 


Surface. 


5 inches. 


Differ- 
ence. 


Soil temperature, 
deep. 


3 inches 


Surface. 


5 inches. 


Differ- 
ence. 


Soil temperature, 
deep. 


1 inches 




6 p. m. 


7 a. m. 


Loss. 


6 p. m. 


7 a. m. 


Loss. 


1 

2 

3 

4 

5 


43.5 
61.6 
42.5 
41.4 
40.0 
42.4 
49.0 
52.2 
53.1 
60.8 
61.5 
62.2 
50.3 
36.2 
47.0 
SB. 5 
60.7 
62.4 
55.4 
56.0 
54.1 
50.7 
46.7 
44.0 
45.0 
45.8 
33.2 
36.7 
43.0 
29. S 


38.8 
60.7 
35.0 
35.0 
32.4 
35.7 
43.4 
46.8 
47.2 
56.0 

ei.8 

59.5 
47.2 
29.3 
45.0 
61.0 
57.4 
58.3 
51.1 
53.3 
49.5 
44.3 
40.2 
37.5 
36.8 
41.5 
27.0 
30.4 
42.0 
2B.S 


-4.7 
-0.8 
-7.5 
-0.4 
-7.6 
-6.7 
-5.6 
-5.4 
-5.9 
-4.8 
+0.S 
-2.7 
-3.1 
-6.9 
-2.0 
-1.5 
-3.3 
-4.1 
-4.3 
-2.7 
-4.6 
-6.4 
-6.5 
-6.5 
-8.S 
-4.3 
-0. 2 
-6.3 
-1.0 
-6.8 


65.3 
62.1 
65.2 
67.0 
67.0 
66.5 
67.8 
69.8 
71.3 
72.8 
71.0 
73. 
09.2 
67.0 
62.2 
61.6 
68.3 
70.3 
71.2 
69.4 
65.4 
07.0 
60.5 
.59.7 
62.5 
63.3 
61.3 
61.0 
57. S 
59.0 


57.8 
62.3 
58.5 
57.3 
57.3 
57.2 
60.3 
61.8 
62.9 
66.3 

er.B 

67. s 
62.5 
55.8 
51.8 
62.1 
64.3 
65.8 
64.7 
63.5 
02.4 
60.8 
57.8 
56.2 
56.4 
59.5 
52.0 
52.7 
56.5 
p. 8 


- 7.5 
+ 0.2 

- 6.7 

- 9.7 

- 9.7 

- 9.3 

- 7.5 

- 8.0 

- 8.4 

- 6.5 

- 3.8 

- 5.8 

- 6.7 
-11. S 
-10.4 
+ O.S 

- 4.0 

- 4.5 

- 6.5 

- 5.9 

- 3.0 

- 6.2 
-2.7 

- 3.5 

- 6.1 

- 3.8 

- 9.3 

- 8.3 

- 1.3 

- 9.2 


37.8 
61.0 
32.2 
34.4 
31.1 
•36.0 
43.2 
46.4 
47.3 
55.2 
62.0 
60.1 
47.3 
29.0 
44.3 
. 6S.0 
57.1 
57.8 
49.2 
54.0 
48.8 
42.8 
40.0 
35.8 
34.0 
38.0 
26.9 
28.4 
35.0 
24. S 


36.0 
61.2 
31.0 
34.0 
30.6 
35.5 
43.7 
47.0 
47.0 
57.8 
57.9 
60.4 
48.3 
28.1 
46.0 
6S.S 
58.0 
58.2 
51.2 
54.1 
50.2 
43.2 
41.1 
36.0 
35.2 
40.3 
25.3 
29.0 
42.2 
20. S 


-1.8 
+0.2 
-1.2 
-0.4 
-0.5 
-0.5 
+0.5 
+0.6 
-0.3 
+2.6 
-4.1 
+0.3 
+1.0 
-0.9 
+ 1.7 
+0.3 
+0.9 
+0.4 
+2.0 
+0.1 
+1.4 
+0.4 
+ 1.1 
+0.2 
+1.2 
+2.3 
-1.6 
+0.6 
+T.S 
-4.0 


61.0 
60.8 
61.8 
61.3 
60.8 
60.3 
60.3 
60.8 
61.4 
62.1 
62.8 
63. 8 
63.8 
62.8 
61.0 
60.3 
61.9 
63.0 
63.7 
63.5 
63.0 
62.8 
61.8 
60.7 
60.1 
59.8 
59.7 


60.7 
61.2 
61.5 
60.8 
60.4 
60.0 
60.4 
61.0 
61.6 
02.5 
63.3 
63. 3 
63.4 
61.6 
60.3 
60.9 
62.4 
63.3 
63.7 
63.2 
62.8 
62.2 
61.1 
60.0 
60.0 
60.2 
58.7 


-0.3 
+0.4 
-0.3 
-0.5 
-0.4 


6 


-0.3 


7 


+0.1 


8 


+0.2 


9 


+0.2 


10 


+0.4 


11 


+0.5 


12 


+0.1 


13 


-0.4 


14 


-1.2 


15.... 


-0.7 


16 


+0.6 


17 . . 


+0.5 


18 


+0.3 


19 


0.0 


20 


-0.3 


21 


-0.2 


22 


-0.0 


23 


-0.7 


24 


-0.7 


25 


-0.1 


26 


+0.4 


27 


-1.0 


28 


58.2 57.7 
S7.S 57.8 
57.8 57.0 


-0.5 


29 


+0.3 


30 


-O.S 


Means 


49.0 


44.2 


-4.8 


65.8 


59.7 


-6.1 


43.4 


43.7 


+0.3 


61.3 


61.1 


-0.2 



Highest and lowest readings are in italics. 



46 

Table 4. — Comparison of Minimum Temperatures at Stations 7 and 7a, Mather, Wis., September, 1900. 



Dav of month. 



1 

2 

3 

4 

5 

C 

S 

9 

10 

11 

12 

13 

14 

15 

IG 

17 

18 

19 

20 

21 

22 

23 

24 

25 

20 

27 

28 

29 

30 

Means 



Surface. 



Station 7. Station 7a. Difference. 



43.5 
61.5 
42.5 
41.4 
40.0 
42.4 
49.0 
52.2 
53.1 
60.8 
61. 5 
62.2 
50.3 
36.2 
47.0 

ei.s 

60.7 
62.4 
55.4 
56.0 
54.1 
50.7 
46.7 
44.0 
45.0 
45.8 
33.2 
36.7 
43.0 
S9.3 



49.0 



37.8 
61.0 
32.2 
34.4 
31.1 
36.0 
43.2 
46.4 
47.3 
55.2 

es.o 

60.1 
47.3 
29.0 
44.3 
62.0 
57.1 
57.8 
49.2 
54.0 
48.8 
42.8 
40.0 
35.8 
34.0 
38.0 
26.9 
28.4 
35.0 
2i.3 



43.4 



- 3.7 

- 0.5 
-10.3 

- 7.0 

- 8.9 

- 6.4 

- 5.8 

- 5.8 

- 5.8 

- 5.6 
+ O.B 

- 2.1 

- 3.0 



- 0.5 

- 3.6 

- 4.6 

- 6.2 

- 2.0 

- 5.3 

- 7.9 

- 6.7 

- 8.2 
-11.0 

- 7.S 

- 6.3 

- 8.3 

- 8.0 

- 5.0 



- 5.6 



5-inch height. 



Station 7. Station 7ii. Difference, 



38. 

60.7 

35.0 

35.0 

32.4 

35.7 

43.4 

46.8 

47.2 

56.0 

61.8 

59.5 

47.2 

29.3 

45.0 

61.0 

57.4 

58.3 

51.1 

53.3 

49.0 

44.3 

40.2 

37.5 

36.8 

41.5 

27.0 

30.4 

42.0 

gl.S 



I 



44.2 



36.0 
61.2 
31.0 
34.0 
30.6 
35.5 
43.7 
47.0 
47.0 
57.8 
57.9 
60.4 
48.3 
28.1 
46.0 
6£.S 
58.0 
58.2 
51.2 
54.1 
50.2 
43.2 
41.1 
36.0 
35.2 
40,3 
25.3 
29.0 
42.2 
20.3 



43.7 



-2.8 
+0.5 
-4.0 
-1.0 
-1.8 
-0.2 
+0.3 
+0.2 
-0.2 
+ 1.8 
-3.9 
+0.9 
+ 1.1 
-1.2 
+ 1.0 
+ 1.3 
+0.6 
-0.1 
+0.1 
+0.8 
+0.7 
-1.1 
+0.9 
-1.5 
-1.0 
-1.2 
-1.7 
-1.4 
+0.2 

— 9 O 



-0.5 



Highest and lowest readings are in italics. 

Minimum temperatures at the coldest and the wannest points on the bog, Mather, Wis. — 
From the foregoino; it is obvious that great extremes of temperature occur in any bog, and 
that there is a wide range in minimum temperature in various portions of the same bog. It 
has, moreover, been found from the discussion of previous tables that at four selected stations 
the exposed minimum surface readings were highest at Station 3 and lowest at Station 5, and 
that at both Stations 3 and 5 the exposed minimum at the 5-incli height registered lower 
than the one at the surface. Stations 2 and 5 were equally cold, Station 5 being in the cran- 
berry bog, in an uncultivated section, while Station 2 was immediately outside, in a field of 
sphagnum moss. The observations at Station 5, although sometimes interrupted by reflowing, 
are preferable in this comparison with Station 3, because of the location of the station among 
the vines. Stations 3 and 5, then, may be considered as being the warmest and the coldest 
places on the bog, and the exposed minimums at these two stations will be discussed in detail; 
first, between the readings of the surface thermometers at both stations during the season 
of 1907; second, between the surface minimum at Station 3 and the minimum at the 5-inch 
height at Station 5 ; and, third, between the last-named readings and the readings of the mini- 
mum in the shelter at Station 1, which, of course, should be the standard for comparison with 
otiier stations. (See Tables 5, 5a, 6, 6a, 7, 7a.) 

The exposed minimums at the surface at Station 3, the thinly vinetl, sanded, and well 
drained section, were usually higher than those at Station 5, over peat and moss, heavily vined 
and with poor drainage. (Table 5.) The difference between the readings gradually but 
irregularly increased from spring to midsummer, after which it decreased until the end of the 
season. The average diiTerence bv months was as follows: May, 3.3°; June, 5.3°; July, 5.7°; 



47 

Aupjust, 4.9°; September, 2.9°; October, 0.8°; while thegjreatest dailj' difference in each month 
was 8.9°, May; 8.8°, June; 9.6°, July; 10.2°, August; 7.1°, September; and 4.3°, October. 
The daily readings at Station 3 were almost invariably much higher than at Station 5, with the 
exception of the month of October; and but three times during May, June, and July tlid the 
instruments at Station 5 register higher than at Station 3. These differences were 0.3° on May 
15, 1° on June 26, and 1.6° on July 22. In August and September there were no instances in 
which the thermometers at Station 5 registered higher than at Station 3, while in October there 
were ten days. The changed relation between tlie readings in October is imdoubtedly tlue to 
the fact that frost had entered the sanded soil at Station 3, as well as the peat soil at Station 5; 
and it is probable, as has been said before, that when once frost enters the soil, its character, 
whether it be peat or sand, is of little consequence in affecting night temperatures. Moreover, 
the vegetation at Station 5 was gradually dying out toward the end of the season, while at 
vStation 3 the conditions changed but little. It is interesting to note that on the coldest day of 
the entire season, October 28, the temperature at Station 3 was 13.9°, 0.3° lower than at Station 5, 
14.2°. In the other months, however, the minimums at the sanded section were several degrees 
higher than in the uncultivated bog. At Station 5 there were several instances of freezing 
temperature during the first decade of June, and one on July 2; on that date the exposed 
minimum at the surface of Station 5 registering 30°, while at the surface at Station 3 the reading 
was 38.8°. Wlienever the readings of the instruments were seriously affected by reflowino- to 
ward off frost, a pi'oper explanation has been made in the tables, and the values of the readmgs 
estimated. It is unfortunate that on September 22, 25, and 26 actual readings of the instru- 
ments at Station 3 were not available, as the portion of the bog in which that station was located 
was covered with water. In Table 5a will be found the niontldy antl the seasonal averages 
for the exposed minimums at the surface of Stations 3 and 5. 

A still further comparison is made in Tables 6 and 6a, showing the difference in readings 
between the surface thermometer at Station 3 and the thermometer at 5 inches at Station 5. 
These may be accepted as being approximately the extremes of minimum temperature to which 
the vegetation in the bog is subjected. The surface minimum at Station 3 averaged higher 
than any other minimum exposed in the open, while the thermometer at 5 inches at Station 5 
averaged the lowest. The average and extreme differences between these instruments were, 
of course, even greater than those noted in the discussion of Table 5. The average seasonal 
difference was 4.4°, and the greatest average monthly difference was 7° in June, while the least 
monthly differences were 3.2° and 3.8° in May and October, respectively. The greatest daily 
difference in May was 7°; in June, 11.9°; July, 11°; August, 12.8°; September, 10.6°; and in 
October, 9°. There were but five instances throughout the entire season when the daily 
minimum at the surface of Station 3 was lower than the upper thermometer at Station 5. The 
lowest reading hi May at the surface at Station 3 was 21.1°, while at 5 inches at Station 5 on 
the same day the reading was 17°; in the other months the lowest readings were respectively 
as follows: June, 33.8° (estimated), and 26.2°; July, 38.8° and 27.9°; August, 42.5° and 33°; 
September, 24.5° and 16.6°; and in October, 13.9° and 6.4°. 
51936°— Bull. T— 10 4 



48 



Table 5. — Comparison of Minimum Temperatures in Open at the Surfaces of Stations 3 and 5, \mth Differ- 
ences. Mather, Wis., 1907. 







May.o 


1 




June. 






July. 






Station 3. 


Station 5. 


Difference. 


Station 3. 


Station 5. 


DiSerence. 


Station 3. 


Station 5. 


Difference. 


1 - - 




» 


- 


34.0 
38.3 
52.9 
43.0 
44.1 
'33.8 
49.5 
36.1 
42.4 
53.7 
44.0 
53.1 
42.6 
39.3 
42.9 
53.5 
86.6 
57.7 
56.3 
51.0 
49.3 
62.3 
60.3 
54.9 
58.9 
49.0 
44.0 
45.0 
50.0 
55.4 


30.9 
29.6 
48.0 
35.5 
42.0 
28.6 
45.2 
SS.I 
34.8 
52.7 
42.7 
51.0 
33.8 
31.0 
41.0 
45.9 
60. S 
.50.4 
47.8 
44.0 
43.8 
59.4 
56.5 
50.4 
56.1 
50.0 
36.8 
37.1 
42.3 
49.0 


-3.1 
— S. 7 
-4.9 
—7.5 
-2.1 
-5.1 
-4.3 
-S.O 
-7.6 
-1.0 
-1.3 
-2.1 
-8.8 
-8.3 
-1.9 
-7.6 
-6. 4 
-7.3 
-8.5 
-7.0 
-5.5 
-2.9 
-3.8 
-4.5 
-2.8 
+1.0 
-7.2 
-7.9 

-6.4 


59.5 
S8.S 
47.2 
51.5 
58.2 
57.9 
50.5 
54.4 
58.8 
50.0 
02.0 
49.6 
52.9 
61.0 
88.9 
54.0 
53.3 
51.2 
56.9 
58.1 
■ 65.9 
■:63.8 
55.0 
62.2 
54.9 
52.8 
47.5 
58.1 
58.0 
50.3 
57.4 


56.0 
SO.O 
40.9 
46.3 
58.0 
53.0 
45.0 
48.2 
51.5 
43.0 
61.3 
43.2 
46.8 
57.0 
86. B 
47.1 
46.7 
43.7 
51.3 
71.0 
60.2 
■165.4 
C47.0 
<:58.2 
C46.8 
C43.2 
C39.2 
54.0 
51.0 
43.0 
50.4 


-3.5 


2 








-8.8 










-6.3 


4 






-5.2 








-0.2 


5 








-4.9 


7 








-5.5 


8 

9 : 

10 








-6.2 
-7.3 








-7.0 








-0.7 


12 

13 


37.3 
68.5 
46.8 
39.0 
.36. 9 
39.0 
41.9 
35.0 
23.7 
11. 1 
44.9 
45.0 
42.1 
45.0 
46.0 

m 
(*■) 

35.9 
43.0 
48.3 


33.9 
SB. 8 
45.2 
39.3 
36.1 
32.4 
34.0 
33.1 
IS. 8 
18.3 
40.8 
43.8 
33.2 
45.0 
45.4 
C) 

33.0 
38.4 
46.7 


-3.4 
-3.7 
-1.6 
+0.3 
-0.8 
-6.0 
-7.9 
-1.9 
-6.9 
-2.8 
-4.1 
-1.2 
-8.9 
0.0 
-0.6 


-6.4 
-6.2 


14 


-4.0 






16 


-6.9 


17 


-6.6 


IS .- 

19 


-7.5 
-5.6 


20 


-7.1 


21 


-5.7 


22 


+1.8 


23 


-8.0 


24 


-4.0 


25 


-8.1 


26 


-9.6 




-8.3 


28 




-4.1 


29 


-2.9 
-4.6 
-1.6 


-7.0 


30 - 


-7.3 


31 


-7.0 












Means 


40.4 


37.1 


-3.3 


48.8 


43.5 


-5.3 


55.5 


49.8 


i -5.7 




1 



■ o Means for eighteen days. ^ Estimated; actual readings valueless on account of reflowing. 

b Readings not obtained; marsh flooded. d Affected by water. 

Station 3. Newly sanded, thinly Tined. ' Station 5. Feat with moss, heavily vined. 

Highest and lowest readings are in italics. 



49 

Table 5. — CoMPAmso>j op Minimi:m Temperatures in Open at Surfaces op Stations :^ and .5, with Differ- 
ences, Mather, Wis.. 1907 — Continued. 



Dav of month. 



August. 



Station 3. Station 5. I Difference. 



1 

2 

3 

4 

5 

6 

7 

8.." 

9 

10 

n 

12 

13 

14 

13 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

Means 



55.1 


50.9 


49.0 


42.2 


47.1 


43.0 


43.1 


.35.0 


r,1.3 


' 58.0 


53. 


46.2 


59.0 


55.0 


56.6 


52.0 


54.0 


49.6 


59.8 


54.0 


68.7 


66.0 


49.7 


43.0 


48.9 


43.0 


52.3 


46.3 


56.6 


50.6 


62.1 


59.0 


51.2 


44.5 


54.8 


50.0 


05.5 


65.0 


46. ft 


.37.9 


48.4 


.38.2 


|S.o 


38.0 


54.0 


48.1 


50.7 


46.1 


42.7 


36.8 


49.8 


43. S 


57.2 


.57.0 


54.0 


52.1 


50.7 


46,0 


62.9 


62.1 


56.3 


54.2 



- 4.2 

- 6.8 

- 4.1 

- 8.1 

- 2.7 

- 6.8 

- 4.0 

- 4.0 

- 4.4 

- 5.8 

- 2.7 

- 6.7 

- 5.9 

- 6.0 

- 6.0 

- 3.1 

- 6.7 

- 4.8 

- 0.5 

- 8.7 
-10.3 

- 4.5 

- 5.9 

- 4.6 

- 5.9 

- 6.0 

- O.S 

- 1.9 

- 4.7 

- O.S 

- 2.1 



September. 



Station 3. Station 5. Difference. 1 Station i Station 5. Difference. 



4.9 



64.1 
53.9 
48.8 
52.7 
46.7 
41.2 
56.5 
57.2 
39.0 
"37.0 
43.7 
43.3 
45.7 
56.5 
57.7 

es.i 

51.0 

59.0 

60.4 

59.4 

,37.4 

O30.3 

41.7 

44.0 

27.2 

<"33.0 

32.7 

38.4 

30.0 

U.5 



October. 



61.4 
46.8 
43.3 
48.8 
42.0 
36.0 
55.6 
56.2 
36.6 
"34.1 
39.2 
40.0 
42.8 
55.0 
54.3 
6i.S 
46.5 
58.6 
59.5 
58.0 
.3.5.2 
24.7 
41.3 
43.3 
24.8 
20.7 
28.8 
38.0 
26.5 



-2.7 
-7.1 
-5.5 
-3.9 
-4.7 
-5.2 
-0.9 
-1.0 
-2.4 
-2.9 
-4.5 
-3.3 
-2.9 
-1.5 
-3.4 
-0.6 
-4.5 
-O.i 
-0.9 
-1.4 
-2.2 
-5.6 
-O.i 
-0.7 
-2.4 
-6.3 
-3.9 
-O.i 
-3.5 
-3.2 





o 


o 


30.8 


28.5 


-2.3 


46.1 


47./ 


+1.0 


41.6 


38.3 


-3.3 


.33.6 


32.0 


-3.5 


36.3 


32.0 


-i.3 


38.7 


37.0 


-1.7 


42.1 


39.7 


-2.4 


21.8 


19.5 


-2.3 


34.6 


35.0 


+ 0.4 


28.5 


28.5 


0.0 


30.1 


30.3 


+0.2 


28.4 


28.7 


+0.3 


19.0 


18.8 


-0.2 


17.7 


18.4 


+0.7 


40.7 


41.8 


+1.1 


33.1 


31.8 


-1.3 


.30.8 


30.5 


-0.3 


23.6 


25.4 


+1.8 


19.7 


18.8 


-0.9 


26.3 


27.0 


+1.3 


17.5 


14.6 


-3.1 


28.5 


27.3 


-1.2 


24.5 


21.8 


-2.7 


21.3 


20.5 


-0.8 


23.6 


23.5 


-0.1 


16.8 


14.7 


-2.1 


32.3 


32.0 


-0.3 


13.9 


H.i 


+0.3 


24.6 


24.4 


-0.2 


36.2 


35.9 


-0.3 


;t 1 II 


30.6 


+0.6 


2s. » 


28.0 


-O.S 



T.\IiLE -Ji;. — MoN'THLV ANI> SEASONAL MeANS, St.ITION'S i? AND 7>. M.\THER, \Vl.«., 1907. 





May.6 


June. 


July. 


August. 


September. 


October. 


Seasonal 
means. 


Surface: 

Station 3 


40.4 
37.1 


o 

48.8 
43.5 


« 

55.5 
49.8 


53.7 
48.8 


45.9 
43.0 


28.8 
28.0 


45.5 


Station 5 


41 7 






Difference 


- 3.3 


- 5.3 


- 5.7 


- 4.9 


- 2.9 


- 0.8 


3.S 







a Estimated; actual readings valueless on account of reflowing. b Means for eiphteen days. 

.Stations. Newly sanded, thinly vined. Stations. Peat with moss, heavily vined. 

Highest and lowest readings are in italics. 



50 



Table 6. — Comparison of Minimum Temperatures in Open at Surface of Station 3, and at 5 Inch^ at Sta- 
tion 5, THE Warmest and Coldest Places on the Marsh, Respectively; also Daily Difference.'!, 
Mather, Wis., 1907. 





May.o 




June. 






July. 




Day of month. 


Station 3— 
surface. 


Station 5— 
5 inclies. 


DiflEer- 
ence. 


Station 3— 
surface. 


Station 5— 
5 inches. 


Differ- 
ence. 


Station 3— 
surface. 


Station 5— 
5 inclies. 


Differ- 
ence. 




o 


„ 


„ 


* 


o 


„ 


o 


o 


. 


1 








34.0 
38.3 
52.9 
43.0 
44.1 
l>33.8 
49.5 
36.1 
42.4 
53.7 
44.0 
53.1 


m.2 

27.9 
46.9 
35.0 
41.5 
l'26.S 
43.8 
26.5 
30.5 
53.0 
38.4 
51.0 


- 7.8 
-10.4 

- 6.0 

- 8.0 

- 2.6 

- 7.0 

- 5.7 

- 9.6 
-11.9 

- 0.7 

- 5.0 

- 2.1 


59.5 
38. 8 
47.2 
51.5 
58.2 
57.9 
50.5 
54.4 
58.8 
50.0 
62.0 
49.6 


55.9 

gr.9 

36.2 
43.9 
59.7 
52.0 
42.5 
49.4 
51.9 
41.0 
00.1 
39.9 


- 3.6 







-10.9 


3 .... _ . . . 




-11.0 






- 7.6 






+ 1.5 


6 . . - . . .... 




- 5.9 


7 




- 8.0 


s 




— 5.0 


q . 


- 6.9 


in 1 


- 9.0 


11 1 .. 


— 1.9 


12 


37. :i 


35.0 


-2.3 


- 9.7 


13 


5G.5 


58.9 


+2.4 


42.6 


32.4 


-10.2 


52.9 


44.0 


- 8.9 


14 


46. S 


45.1 


-1.7 


39.3 


29.6 


- 9.7 


61.0 


56.8 


- 4.2 


15 


39.0 


36.9 


-2.1 


42.9 


34.0 


-8.9 


68.9 


67.1 


- 1.8 


16 


36.9 


34.8 


-2.1 


53.5 


45.5 


-8.0 


54.0 


45.3 


- 8.7 


17 - 


39.0 


33.0 


-6.0 


6S.S 


6S.S 


- 4.1 


53.3 


45.0 


- 8.3 


18 


41.9 


39.1 


-2.8 


57.7 


48.9 


- 8.8 


51.2 


42.6 


- 8.6 


19 


35.0 
2.3.7 


31.0 
19.3 


-4.0 
-4.4 


56.3 
51.0 


48.7 
42.4 


- 7.6 

- 8.6 


56.9 
58.1 


51.0 
51.3 


- 5.9 


20 


- 6.8 


21 


.'/.; 


n.o 


-4.1 


49.3 


40.3 


- 9.0 


65.9 


59.9 


- 6.0 


22 


44.9 


42.0 


-2.9 


62.3 


59.0 


- 2.7 


663.8 


61.9 


- 1.9 


23 


45.0 


43.7 


-1.3 


60.3 


55.2 


- 5.1 


55.0 


i>45.9 


- 9.1 


24 


42.1 


34.0 


-8.1 


54.9 


49.5 


- 5.4 


62.2 


1.57.1 


- 5.1 


25 


45.0 


43.8 


-1.2 


58.9 


53.1 


- 5.8 


54.9 


645.7 


— 9.2 


26 


46.0 


45.0 


-1.0 


49.0 


45.7 


- 3.3 


52.8 


6 42.1 


-10.7 


27 


(') 


(.') 




44.0 


34.0 


-10.0 


47.5 


40.0 


- 7.5 


28 


(<■) 


W 




45.0 


35.2 


- 9.8 


58.1 


53.2 


- 4.9 


29 


35.9 
43.0 
48.3 


29.3 
36.0 
45.9 


-6.6 
-7.0 
-2.4 


50.0 
56.4 


. 41.1 
47.4 


- 8.9 

- 8.0 


58.0 
50.3 
57.4 


51.5 
41.6 
50.0 


- 0.5 


30 


- 8.7 


31 


- 7.4 














40.4 


37.2 


-3.2 


48.8 


41.8 


- 7.0 


55.5 


48.8 


- 6.7 







a Means for eighteen days. 

6 Estimated; actual readings valueless, on account of reflowing or heavy rains. 

c Readings not obtained; marsh flooded. 

Station 3. Xewly sanded, thinly vined. Station 5. Peat with moss, heavily vined. 

Highest and lowest readings are in italics. 



51 

Table 6. — Comparison of Minimum Temperatures in Open at Surface of Station 3, and at 5 Inches at 
Station 5, the Warmest and Coldest Places on the Marsh, Respectively; also Daily Differences, 
Mather. Wis., 1907 — Continued. 



Dav of month. 



August. 



September. 



Station 3- 
j surface. 



1 

2 

3 

4 

5 

0. 

7 

8 

9 

lU 

11 

12 

13 

14 

15 

Id 

17 

18 

19 

20 

21 

22 

23 

24 

•25 

20 

27 

28 

29 

30 

31 

Means. 



55.1 
49.0 
47.1 
43.1 
61.3 
53.0 
59.0 
56.6 
54.0 
59.8 

es.r 

49.7 
48.9 
52.3 
50.6 
62.1 
51.2 
54.8 
65.5 
46.6 
48.4 
4£.S 
54.0 
50.7 
42.7 
49.8 
57.2 
54.0 
.50.7 
62.9 
56.3 



Station 5 — 
5 inches. 



53.7 



44.0 
40.9 
41.9 
S3.0 
38.0 
44.8 
54.0 
50.1 
48.0 
53.0 
89.0 
41.0 
40.6 
45.0 
50.2 
38.6 
43.6 
46.7 
64.8 
34.8 
35.6 
33.6 
46.1 
44.3 
33.3 
41.0 
55.6 
50.5 
44.0 
62.6 
52.7 



Differ- 
ence. 



-11.1 

- 8.1 

- 5.2 
-10.1 

- 3.3 

- 8.2 

- 3.0 

- 6.5 

- 6.0 

- 6.8 
+ O.S 

- 8.7 

- 8.3 

- 7.3 

- 6.4 

- 3.5 

- 7.6 

- 8.1 

- 0.7 
-11.8 
-IS. 8 

- 8.9 

- 7.9 

- 6.4 

- 9.4 

- 9.8 

- 1.6 

- 3.5 

- 6.7 

- 0.3 

- 3.6 



Station 3- 
siirface. 



M. 1 
53.9 
48.8 
32.7 
46.7 
41.2 
56.5 
57.2 
39.0 

"37.0 
43.7 
43.3 
45.7 
56. 5 
57. 7 
65.1 
51.0 
.59. 
(JO. 4 
59.4 
.37.4 

"30.3 
41.7 
44.0 

a 27. 2 

"3.3.0 
32.7 
38.4 
30.0 



Station .5- 
5 inches. 



61.7 
43.5 
41.3 
48. 8 
41.3 
32.6 
35.5 

"50.8 
33.7 

" 32. 3 
36.5 
37.0 
39.7 
.54.9 
53.0 
64.5 
43.5 
56.1 
68. S 
56.2 
31.1 
19.7 
39.0 
41.7 
20.0 
22. 6 
20.1 
36.9 
23.3 
16. 6 



47.1 



6, 6 



Differ- 
ence. 



-2.4 
-8.4 

- 7. 5 
-3.9 
-5.4 
-8.6 

- 1.0 

- 6.4 
-5.3 
-4.7 

- 7. 2 

- 6.3 
-6.0 

- 1.6 
-4.7 
-0.6 

- 7.5 
-2.9 

- i.e 

-3.2 
-6.3 
-10.6 
-2.7 
-2.3 

- 0.6 
-10.4 
-6.6 
-1.5 
-6.7 
-7.9 



- 5.2 



October. 



Station 3- 
snrface. 



30.8 
46.1 
41.6 
33.5 
36. 3 
38.7 
iJ.O 
21.8 
34.6 
28.5 
30.1 
28.4 
19.0 
17.7 
40.7 
33.1 
30.8 
23.6 
19.7 
26.3 
17.5 

28. 5 
24.5 
21.3 

23. 6 
16.8 
32.3 
13.9 
24.6 
36.2 
30.0 



Station 5- 
5 inches. 



28.8 



25.6 
46.7 
35.5 
29.3 
30.3 
35.6 
38.0 
12.8 
34.0 
24.8 
28.3 
25.9 
12.0 
12.4 
il.S 
29.4 
28.4 
20.7 
13. S 
23.5 

9.8 
26.5 
18.8 
14.7 
21.5 

9.3 
31.6 

6.4 
21.7 
35.7 
29.5 



25.0 



Differ- 
ence. 



-5.2 
+0.6 
-6.1 
-4.0 
-6.0 
-.3.1 
-4.0 
-9.0 
-0.6 
-3.7 
-1.8 
-2.5 
-7.0 
-5.3 
+0.8 
-3.7 
-2.4 
-2-9 
-5-9 
-2.8 
-7.7 
-2.0 
-5-7 
-6.0 
-2.1 
—7.5 
-0-7 
-7.5 
-2.9 
-05 
-0-5 



-3.8 



Table (in. — Monthly and Seasonal Mean.s. St.4.tion 3, Surface, and St.\tion 5, 5 Inches. Mather. Wis. 

1907. 





Ma.v.l> 

40.4 
37.2 


June. 


.Tuly. 


.Vugnst. 


September. 


October. 


Seasonal 
means. 




48.8 
41.8 


55.3 
48.8 


53.7 
47.1 


45.9 
40.7 


28.8 
25.0 


45.3 
40.1 


Station 5 — 5 inches . 




Diflerence 


-3.2 


-7.0 


-6.7 


-6.6 


- 5.2 


- 3.8 


- 5.4 





" Estimated: actual readings valueless, on account of reflowing or heavy rains. b Means for eighteen days. 

Station 3. Xewly sanded, thinly vined. Station 5. Peat with moss, heavily vined. 

Highest and lowest n-adings are in italics. 



52 

Comparison of minimum temperatures at Station 1 , in sJielter, and on hog at Stations S and 3, 
Mather, Wis. — While the comparisons made in Tables 5 ami 6 have been between the warmo>st 
and the coldest stations on the bog, the tejuperature in the shelter at Station 1 on the upland 
may properly be considered the standard, and a comparison between the thermometer therein 
and one in the open at the height of 5 inches at Station 5 and tlie one at the surface at Station 3 
should be of special interest. Of course, the exposed minimum at Station 5 was much lower 
than the one' in the shelter at Station 1, the average difference being 6.7°. (See Tables 7 and 
7a.) The least monthly average difl'erence was 4.5° in May, and the greatest 8. .3°, in October. 
The greatest daily difference in May was 12° on the 29th; in June, 11° on the 27th; in July, 
12° on the 3d; in August, 14.2° on the 25th; in September, 1 1.6° on the 22d; in October, 14.6° 
on the 24th. With but few exception the temperature at Station 5 was lower than at -Station 1 
and markedly so on clear, cool nights. When the sky was overcast and the night windy the 
difference was much less. 

The comparison between the shelter at Station 1 and the surface at Station 3, however, 
aft'ords far different results. The temperature at Station 3 was, as a rule, only slightly below that 
in tlie shelter at Station 1 , the seasonal average difference being 1 .3°. In the summer the differ- 
ence was very little, being only 0.1° and 0.2°, but it was greater in the spring and in the fall, espe- 
cially in October when the average tlifference was 4.5°. At Station 5, as has been statetl before, 
the difference was 8.3° for October. It is probable that these great differences in October were 
due to the number of comparatively cool nights which were gradually increasing in length and 
which affortled a longer period for radiation and consecjuent loss of heat from vegetation. The 
daily differences between the readings in the shelter at Station 1 and those in the open at Station 
3, the sanded section, were often unimportant, and on many tiays tiiere was a reversal, the tem- 
perature aetually reading higher over the sanded section in the hog, especially in the summer motiths. 
This inversion occurred on fourteen days in June, fourteen days in July, fifteen days in August, 
ten days in September, hut in no instance in October. These results — the comparatively high 
miniuuim temperatures at the surface of the sanded bog — realty seem remarkable, and could 
hardly be believed unless great care iiad been taken in the observations. In this connection 
it is interesting to note that the mininuim temperature in tlie shelter at Station 3 averageil 
for the season only 0.5° below that in the shelter at Station 1, while the minimiun in the shelter 
at Station 5 averaged 3.1° below that in the shelter at Station 1. (See Table 18.) The advan- 
tages gained by sanding are still further emphasized by observations made at Berlin, Wis., 
where the exposed minimum at the surface of a sanded section during the montii of Se])tember, 
1906, actually averaged higher by 0.5° than the minimum in the shelter at Station 1 , on adjoining 
hard land, while the exposed minimum at the 5-inch height at Station 5, the coldest point on 
the Berlin bog, averaged 9.5° lower than that in the shelter at Station 1. (Table 9.) 

From the comparison of these observations made at Stations 3 and 5, at Mather, it should 
be apparent that a thinly vined, sanded, and well drained soil is a most important factor in 
conserving heat — in strong contrast with a heavily vined moss-covered surface which absorbs 
but little heat, and at the same time radiates rapidly. 



53 



Table 7.— Comparison of Min'1.uum Temperatures in Shelter at Station 1, and in Open at 5-inch Height at 
Station 5, the Coldest Place on the Marsh, and in Open .at Surface at Station 3, the Warmest Place on 
the Marsh, Illustrating the Advantages obtained from Sanding, Draining, and Cultivating, Mather, 
Wis., 1907. 





May. 






June. 






Day of month. 


Station 1— 
shelter. 


Station 5— 
5 inclies 

above sur- 
face ex- 
posed. 


Difference. 


Station 3— 
.surface 
exposed. 


DiSer- 

ence— 

Stations 1 

and S. 


Station 1— 
shelter. 


Station 5— 
5 inches 

above sur- 
face ex- 
posed. 


j 
Difference. 


Station 3- 
surface \ 
exposed. 


Differ- 
ence — 
Stations 1 
and 3. 




= 


- 


' 


= 


' 


36.0 

38.7 

50.1 

41.2 

44.4 

SJ,.0 

47.6 

36.0 

41.0 

54.5 

47.0 

52.8 

43.7 

38.9 

43.0 

53.8 

70.0 

58.6 

57.0 

50.6 

48.7 

61.4 

60.2 

54.0 

57.8 

48.2 

45.0 

43.0 

51.0 

58.0 


26.2 

27.9 

46.9 

35.0 

41.5 

32.5 

43.8 

26.5 

30.5 

63.0 

38.4 

51.0 

32.4 

29.6 

34.0 

45.5 

62.5 

48.9 

48.7 

42.4 

40.3 

59.6 

55.2 

49.5 

63.1 

45.7 

34.0 

35.2 

41.4 

47.4 


- 9.8 
-10.8 

- 8.2 

- 6.2 

- 2.9 
-US 

- 3.8 

- 9.5 
-10.5 

- 1.5 

- 8.6 

- 1.8 
-11.3 

- 9.3 

- 9.0 

- 8.3 

- 7.5 

- 9.7 

- 8.3 

- 8.2 

- 8.4 

- 1.8 

- 5.0 

- 4.5 

- 4.7 

- 2.5 
-II. 

- 7.8 

- 9.6 
-10.6 


4.0 
38.3 
52.9 
43.0 
44.1 
SS.8 
49.5 
36.1 
42.4 
63.7 
44.0 
53.1 
42.6 
39.3 
42.9 
53.5 
66.6 
57.7 
56.3 
51.0 
49.3 
62.3 
60.3 
54.9 
58.9 
49.0 
44.0 
45.0 
50.0 
55.4 


- 2.0 














- 0.4 














- 2.2 














-1- 1.8 














- 0.3 














- 0.2 


"_ 












+ 1.9 














-1-0.1 






'. 








-1-1.4 






A 








- 0.8 














-3.0 


12 


36.2 
610 
44.7 
36.0 
35.0 
40.0 
47.7 
38.8 
27.5 

er.s 

45.0 
44.0 
43.6 
45.0 
43.3 
<i32.5 
a 34.1 
41.3 
44.6 
47.0 


35.0 
68.9 
45.1 
36.9 
34.8 
33.0 
39.1 
31.0 
19.3 
17.0 
42.0 
43.7 
34.0 
43.8 
45.0 

29.3 
36.0 
45.9 


- 1.2 

- 5.1 
-t- 0.4 
-1- 0.9 

- 0.2 

- 7.0 

- 8.6 

- 7.8 

- 8.2 
-10.3 

- 3.0 

- 0.3 

- 9.6 

- 1.2 
+ 1.7 


37.3 
56.5 
46.8 
39.0 
36.9 
39.0 
41.9 
35.0 
23.7 
21.1 
44.9 
45.0 
42.1 
45.0 
46.0 
{») 

m 

35.9 
43.0 
48.3 


+ 1.1 

- 7.5 
+ 2.1 
+ 3.0 
+ 1.9 

- 1.0 

- 5.8 

- 3.8 

- 3.8 

- 6.4 

- 0.1 
-1- 1.0 

- 1.5 
0.0 

-1-2.7 


-1- 0.3 




- 1.1 


14 


-1-0.4 


15 

in 

17 


- 0.1 

- 0.3 
-S.i 

- 0.9 


19 

20 


- 0.7 
-1- 0.4 


21 


-I- 0.6 


22 


-1- 0.9 


23 


-1- O.l 


24 


-1- 0.9 


25 


-1- 1.1 


26 


+ 1.2 




- 1.0 








+ 2.0 


29 


-12.0 

- 8.6 

- 1.1 


- 5.4 

- 1.6 
-1- 1.3 


- 1.0 


30 


- 2.6 


31 




Means 


41.7 


37.2 


-4.5 


40.4 


- 1.3 


49.0 


41. S 


— 7 2 


48.8 


1 - 0.2 







" Not included in average. 

Station 1. On upland. 

Station 3. Thinly vined, newly sanded, and well drained section of luarsh. 

Station 5. Heavily vined, peat with moss, and poorly drained section of marsh. 

Highest and lowest readings are in italics. 



b Under water. 



54 

Table 7. — Comparison of Minimum Temperatures in Shelter at Station 1. and in Open at 5-inc^Height at 
Station 5, the Coldest Place on the Marsh, and in Open at Surface at Station 3, the Warmest Place 
ON the Marsh, Illustrating the Advantages obtained from Sanding, Draining, and Cultivating, Mather, 
Wis., 1907— Continued. 





July. 






August. 






Day or montli. 


Station 1— 
shelter. 


Station 6-r 
5 inches 

above sur- 
face ex- 
posed. 


Diflerence. 


Station 3— 
surface 
exposed. 


Differ- 
ence- 
Stations 1 
and 3. 


Station 1— 
shelter. 


Station 5— 
6 inches 

above sur- 
face ex- 
posed. 


Diflerence. 


Station 3— 
surface 
exposed. 


Difler- 
ence— 
Stations 1 
and 3. 


1 


59.1 
SS.3 
48.2 
51.0 
60.2 
58.2 
50.7 
59.4 
61.0 
50.0 
60.0 
51.3 
■53.8 
62.4 
68. S 
51.0 
56.8 
50.4 
56.0 
61.0 
64.2 
64.0 
52.8 
64.0 
52.6 
49.0 
45.0 
58.9 
56.7 
53.0 
67.6 


55.9 
17.9 
36.2 
43.9 
59.7 
52.0 
42.5 
49.4 
51.9 
41.0 
60.1 
39.9 
44.0 
56.8 
67.1 
45.3 
45.0 
42.6 
51.0 
51.3 
59.9 
61.9 
"45.9 
57.1 
45.7 
a 42.1 
40.0 
53.2 
51.5 
41.6 
50.0 


- 3.2 
-10.4 
-12.0 

- 7.1 

- 0.5 

- 6.2 

- 8.2 
-10.0 

- 9.1 

- 9.0 
+ 0.1 
-11.4 

- 9.8 

- 5.6 

- 1.2 

- 5.7 
-11.8 

- 7.8 

- 6.0 

- 9.7 

- 4.3 

- 2.1 

- 6.9 
-6.9 

- 6.9 

- 6.9 

- 6.0 

- 5.7 

- 5.2 
-11.4 

- 7.6 


69.5 
38.8 
47.2 
51.5 
58.2 
57.9 
50.5 
54.4 
58.8 
50.0 
62.0 
49.6 
52.9 
61.0 
68.9 
54.0 
53.3 
51.2 
.56.9 
58.1 
66.9 
63.8 
5,6.0 
62.2 
54.9 
52.8 
47.5 
58.1 
68.0 
50.3 
57.4 


+ 0.4 
-1- 0.5 

- 1.0 
+ 0.5 

- 2.0 

- 0.3 

- 0.2 

- 5.0 

- 2.2 


-1- 2.0 

- 1.7 

- 0.9 

- 1.4 
-1- 0.6 
-1- 3.0 

- 3.5 
-1- 0.8 
-1- 0.9 

- 2.9 
+ 1.7 

- 0.2 
-1- 2.2 

- 1.8 
+ 2.3 
-1- S.8 
+ 2.5 

- 0.8 
+ 1.3 

- 2.7 

- 0.2 


65.0 
45.8 
48.1 
38.9 
59.2 
54.0 
57.0 
55.0 
52.8 
59.0 
71 S 
52.7 
50.0 
52.8 
56.1 
61.2 
52.2 
57.0 
65.0 
43.0 
47.0 
43.0 
63.7 
54.1 
47.5 
50.7 
55.5 
58.0 
51.2 
64.0 
58.3 


44.0 
40.9 
41.9 
SS.O 
58.0 
44.8 
54.0 
50.1 
48.0 
j|.0 
69.0 
41.0 
40.6 
45.0 
50.2 
68.6 
43.6 
46.7 
64.8 
34.8 
35.6 
33.6 
46.1 
44.3 
33.3 
41.0 
55.6 
50.5 
44.0 
62.6 
52.7 


-11.0 

- 4.9 

- 7.2 

- 5.9 

- 1.2 

- 9.2 

- 3.0 

- 4.9 

- 4.8 
-6.0 

- 5.2 
-11.7 
-9.4 

- 7.8 

- 5.9 

- 2.6 
-8.6 
-10.3 

- 0.2 

- S.2 
-11.4 

- 9.4 

- 7.6 

- 9.8 
-U.S 

- 9.7 
-1- 0.1 

- 7.6 

- 7.2 

- 1.4 

- 5.6 


55.1 
49.0 
47.1 
43.1 
61.3 
53.0 
59.0 
56.6 
54.0 
59.8 
68.7 
49.7 
48.9 
52.3 
66.6 
62.1 
61.2 
54.8 
65.5 
46.6 
48.4 
i^.S 
54.0 
60.7 
42.7 
49.8 
57.2 
54.0 
60.7 
62.9 
56.3 


+ 0.1 


2 


-t- 3.2 


3 

4 

5 

6. 


- 1.0 

-1- i.2 
+ 2.1 

- 1.0 


7 


-F 2.0 

-f l.r, 


9 


-1-1.2 


10 


-1-0.8 


11 


- S.5 


12 


- 3.0 


13 - 

14 


- 1.1 

- 0..3 


15 


-1-0.5 


16 


4- 0.9 


17 


- 1.0 


18 


- 2.2 


19 


-1-0.5 


20 


+ 3.1) 


21 


+ 1.4 


22 


- 0.5 


23 


4-0.3 


24 


- 3.4 


25 


- 4.S 


26. 


- 0.9 


27 


-1- 1.7 


28 


- 4.0 


29 


- 0.3 


30 


- 1.1 


31 


- 2.0 




55.6 


48.8 


- 6.9 


55.0 


- 0.1 


53.9 


47.1 


- 6.8 


53.7 


- 0.2 







a Not included in average; affected hy water. 

Station 1. On upland. 

Station 3. Thinly vined, newly sanded, and well drained section of marsh. 

Station 5. Heavily vined, peat with moss, and poorly drained section of marsh. 

Highest and lowest readings are in italics. 



55 

Table 7. — Comparison of Minimum Temperatures in Shelteh at St.\tion 1, and in Open at 5-inch Height at 
Station 5, the Coldest Place on the Marsh, and in Open .\t Surface at Station 3, the Warmest Place 
ON THE Marsh. Illustrating the Advantages obtained fro.m Sanding, Draining, and Cultivating, 
Mather, Wis., 1907 — Continued. 









September. 






October. 


Day of month. 


.Station I — 
shelter. 

70.0 
53.1 
50.5 
52.0 
44.2 
41.0 
54.0 
5(i.5 
40.0 
38.0 
45.0 
48.0 
49.9 
62.0 
63.0 
66.6 
53.0 
57.9 
61.3 
59.9 
37.9 
31.3 
44.6 
43.2 
28.2 
34.0 
33.7 
37.0 
29.2 
17.5 


Station 5— 
5 inches 

above sur- 
face ex- 
posed. 

61.7 
45.5 
41.3 
48.8 
41.3 
32.6 
.55.5 

O30.8 
33.7 

"32.3 
36.5 
37.0 
39.7 
54.9 
53.0 
SI 5 
43.5 
56.1 
58.8 
56.2 
31.1 
19.7 
39.0 
41.7 
20.6 
22.6 
26.1 
36.9 
23.3 
16.6 


Difference. 


Station 3— 
surface 
exposed. 


Differ- 
ence — 
Stations 1 
and 3. 


Station 1- 
shelter. 


Stations— 

5 inches 
above sur- 
face ex- 
posed. 


Difference. 


Station 3— 
surface 
exposed. 


Differ- 
ence — 
Stations 1 
and 3. 


1 


- 8.3 

- 7.6 

- 9.2 

- 3.2 

- 2.9 

- 8.4 
+ 1.5 

- 5.7 

- 6.3 

- 5.7 

- 8.5 
-11.0 
-10.2 

- 7.1 
-10.0 

- 2.1 

- 9.5 

- 1.8 

- 2.5 

- 3.7 

- 6.8 
-11.6 

- 5.6 

- 1.5 

- 7.6 
-11.4 

- 7.6 

- 0.1 

- 5.9 
-10.9 


64.1 
53.9 
48.8 
52.7 
46.7 
41.2 
56.5 
57.2 
39.0 

037.0 
43.7 
43.3 
45.7 
56.5 
.57.7 
65.1 
51.0 
59.0 
60.4 
59.4 
37.4 

030.3 
41.7 
44.0 

027.2 

033.0 
32.7 
38.4 
30.0 
U.5 


-5.9 
+0.8 
-1.7 
+0.7 
+ 1.5 
+0.2 
+S.5 
+0.7 
-1.0 
-1.0 
-1.3 
-4.7 
-4.2 
-5.5 
-5.3 
-1.5 
-2.0 
+1.1 
-0.9 
-0.5 
-0.5 
-1.0 
-2.9 
+0.8 
-1.0 
-1.0 
-1.0 
+1.4 
+0.8 
-3.0 


33.0 
51.5 
45.6 
41.0 
41.2 
44.0 
49.5 
22.8 
40.0 
34.6 
34.6 
29.3 
24.6 
22.5 
44.0 
35.5 
38.6 
24.2 
27.3 
27.5 
19.0 
40.0 
29.6 
29.3 
27.6 
18.9 
34.0 
17.0 
3.25 
37.2 
36.8 

33.3 


25.6 
46.7 
35.5 
29.5 
30.3 
35.6 
38.0 
12.8 
34.0 
24.8 
28.3 
25.9 
12.0 
12.4 
41.5 
29.4 
28.4 
20.7 
13.8 
23.5 

9.8 
26.5 
18.8 
14.7 
21.5 

9.3 
31.6 

e-i 

21.7 
35.7 
29.5 


- 7.4 

- 4.8 
-10.1 
-11.5 
-10.9 

- 8.4 
-11.5 
-10.0 

- 6.0 

- 9.8 

- 6.3 

- 3.4 
-12.6 
-10.1 

- 2.0 

- 6.1 
-10.2 

- 3.5 
-13.5 

- 4.0 

- 9.2 
-13.5 
-10.8 
-li.6 

- 6.1 

- 9.6 

- 2.4 
-10.6 
-10.8 

- I.S 

- 7.3 


30.8 
46.1 
41.6 
33.5 
36.3 
38.7 
42.0 
21.8 
34.6 
28.5 
30.1 
28.4 
19.0 
17.7 
40.7 
33.1 
30.8 
23.6 
19.7 
26.3 
17.5 
28.5 
24.5 
21.3 
23.6 
16.8 
32.3 
IS. 9 
24.6 
36.2 
30.0 


— 2. 2 


2 


- 5.4 


3... 


- 4.0 


4 


- 7.5 


5 


- 4.9 


6 


- 5.3 


8 


- 1.0 


9 


- 5.4 


10 


- 6.1 


11.. . 


- 4.5 


12 


- 0.9 


13 


- 5.6 


14 


- 4.8 


15 


- 3.3 


16 


- 2.4 


17 


- 7.8 


18 


- 0.6 


19 


- 7.6 


20.. 


- 1.2 


21 


- 1.5 


22 


-11.5 


23 


- 5.1 


24 


- 8.0 


25.. . 


- 4.0 


26 


- 2.1 


27 


- 1.7 


28 


- 3.1 


•29 


- 7.9 


30 


- 1.0 

- 6.8 














Means 


47.1 


40.7 


- 6.4 


45.9 


-1.2 


25.0 


- 8.3 


28.8 


-4.5 



a Estimated; actual readings valueless on account of reflowing or heavy rains. 
Station 1. On upland. 

Station 3. Thinly vined, newly sanded, and well drained section of marsh. 
Station 5. Heavily vined, peat with moss, and poorly drained section of marsh. 

Table 7a. — Monthly and Seasonal Means of Table 7. 





May.o 


June. 


July. August. 


September. 


October. 


Seasonal 
means. 


Stition 1 shelter 


41.7 
37.2 


49.0 
41.8 


55. 6 53. 9 
48. 8 47. 1 


47.1 3.3.3 
40.7 1 25.0 


46.8 




40.1 










-4.5 
40.4 


-7.2 
48.8 


-6.8 
55.5 


—6.8 —6.4 -8.3 
53. 7 45. 9 28. 8 


-6.7 




45.5 








-1.3 ' -0.2 -0.1 


-0.2 -1.2 -4.5 -1.3 



















o Means for eighteen days. 
Highest and lowest readings are in italics. 



56 

Curves of air and soil temperatures at Stations 1, 3, and 5, Mather, Wis., 1907. — Ii»order to 
indicate more CTrapliically the relation existing: between tlie air temperature and the temperature 
of the soil at the depth of 3 inches, and also between the soil temperatures at depths of 3 and 6 
inches, Figures 21 and 22 have been prepared, showing curves for the season of 1907. The 
maximum temperature given is that recorded in the shelter at Station 1, equally applicable 
to Stations 3 and 5, and may be considered to represent in a measure the amount of insolation 
received from day to day. These graphs should supplement Tables 3, 5, 6, and 7. 

From the beginning of the season and until midsummer the temperature of the soil at both 
Stations 3 and 5 rose graduallj^ apparently in direct proportion to the amount of heat which the 
different soils absorbed and conducted under the varying conditions of covering as regards 
vegetation, etc. The temperature of tiie soil at the 3-inch depth at Station 3, the sanded and 
thinly vined section, responded quickly to the various changes in insolation, and the range in 
soil temperature at this depth was relatively great from day to day, because of the slight depth 
at which the bulb of the soil thermometer was exposed, and also because of the good conductivity 
of the sanded soil. At the 6-inch de])th at the same station the changes in temperature followed 
closelj' those at the 3-inch depth, but on account of the additional 3 inches in depth the changes 
from da}' to day were not so marketl. At Station .5, peat soil with moss and dense vegetation, 
the .temperature at 3 inches responded but slowly to changes in temperature of the air, because 
of the poor conductivity of the soil, and the fact that tlie dense growth of vegetation prevented 
the soil from absorbing much heat from the sun's rays. At the 6-inch depth the changes 
from day to day were even less. It is interesting here to note that, because of the dense vege- 
tation and greater depth and the fact that the little heat received at the surface of the peat was 
conducted slowly to the soil beneath, the maximum heat of one day was not felt at the 6-inch 
depth at Station 5 until the day following. Tliis lagging of the ma.ximum heat is also noted 
at the 3-inch depth at the same station, but in a lesser degree, while almost invariably the maxi- 
mum heat of one day was conducted on the same day to both depths at Station 3, the sanded 
section. These variations in soil temperature are shown graphically on May 19 and 30, June 
7 and 19, July 6, August 11, and September 1. In this connection it may be noted that sudden 
falls in temperature of the air, as shown by the minimum temperature curves (Fig. 21), were 
felt but little at either depth at Station 5, and on Julj' 21, while the temperature of the soil at 
botli depths at Station 3 fell in response to a sudden decline in temperature of the air, the tem- 
perature of the soil at the depth of 6 inches at Station 5 was not influenced in the least, but even 
continued to rise gradually, the maximum heat recorded at the two first-named locations on 
July 20 not being felt at the 6-inch depth until the 22d, two days later. 

Until the latter part of July the difference between the soil temperatures at the various 
depths was remarkably uniform. (Fig. 22.) From this tune on until the end of the season 
the lines representing the seasonal march of soil temperature lose the relative positions which 
they occupy during the first part of the season. This is on account of the gradual approach of 
longer nights and shorter days with their attendant colder weather, so that more heat was lost 
from the sanded surface and less heat taken in, in proportion, than was lost and taken in 
by the feat soil. Hence, while a large amount of heat was lost each night from the feat 
soil, an even larger amount was lost from the sanded surface itself. On account of the greater 
susceptibility of the sand to changes in insolation as compared with that of the heavily vined 
peat soil, and because the heat in the peat which accumulates during the warm months is 
not lost as quickly as that in the sanded soil, we find the temperature of the soil on cold 
nights at both depths at Station 3 falling below the temperature of the soil at both depths at 
Station 5. These changes were apparent as early as August 1, when under the influence of a 
cool day, the soil temperature in the sanded section fell so much more than did the temperature 
in the peat soil, that the readings at all exposures were about the same, the temperature at 
6 inches at Station 3 being 1° lower than at the corresponding depth at Station .5. Other such 
changes are well shown on August 20 and 26, September 3 and 21. On September 25, under the 
influence of continued cool weather, the temperature at both depths at Station 3 fell below 
that at both deptiis at Station 5 for the first time during the autumn. This is also noted on 
October 9, 12, 19, and 27. 



57 




58 



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From a study of the graph, as showiwin Figure 
21, it is extremely interesting to note the tend- 
ency of the soil temperature during tlie months 
of August and September at the 3-inch dejith at 
Station 5 to fall below that at the 6-inch depth 
at the same station, and it was noted to be 
actualh' lower for the first time on September 5. 
From the 20tli on the readings at the former 
depth were almost continuously below those at 
the latter depth. In fact, by referring to Table 
19, it will l)e found that tiie soil temperature 
at 6 inches at Station 5 began to gain on the 
temperature at 3 inches at the same station as 
early as July, and by the following amounts: 
Juty, 0.6°; August, 0.8°; September, 1.2°; Octo- 
ber, 1.3°. This is because after a certain date, 
apparently late in July, the temperature of the 
soil at 3 inches began to decrease while that at 
6 inches began to decrease also, but more slow- 
ly; so that during the month of October the 
temperature at the 6-inch depth was usually 
higher than at the 3-inch depth. This shows 
that while the peat soil at 6 inches under a thick 
growth of vegetation takes a longer time to 
become heated than at the three other locations, 
it retains its heat longer. The reason that gen- 
erally during October the soil temperature at 3 
inches at Station 5 was the lowest of the four 
exposures, with the readings at 6 inches be- 
tween it and the 3-inch depth at .Station 3, was 
probably because that, although it was not as 
easily influenced by the insolation as that at 
vStation 3, still the temperature at 3 inches at 
Station 5 was not nearly as high even in mid- 
summer, so that when cool weather approached 
it remained relatively low. On the other hand, 
tlie temperature at 3 inches at Station 3 was 
lower during cool, cloudy weather, and warmer 
during warm, sunshiny days; at the same time 
the temperatures at 6 inches took intermediate 
values because of their greater depth and conse- 
quent slower changes. 

Minimum tem-peratures at the coldest and the 
warmest points on the hog at Berlin, Wis. — It is 
po,ssible to make a comparison between the read- 
ings of the minimum thermometers exposed in 
the bog at places at Berlin, that are considered 
the warmest and the coldest referred to in pre- 
vious paragraphs, and also to compare these 
readings with the readings of a thermometer 
in a shelter on hard land on the edge of the 
bog. The readings are found in Tables S and 9, 
and, although given only for the month of Sep- 
tember, 1906, will serve to supplement the Mather 



59 

observations. Station 3 at Berlin was located in a newly sanded, thinly vined, and well drained 
section, similar to Station 3 at Mather, while Station 5 at Berlin was in the midst of a dense 
growth of vegetation, includmg vines, grasses, canebrakes, and ferns. In fact, this station was 
commonly called the "ferns." The uprights from the vines reached to a height of from 12 to 
18 inches. It was a wild place, not resembling the conditions one would expect to find in a 
cultivated cranberry marsh; but cultivation was not practiced in reality at Berlin. Although 
it was the coldest point in the Berlin bog, the vegetation there was not similar to that prevailing 
at Station .5 at Matlier. Wliile moss, which is largely responsible for low night temperatures, 
was found at Mather, there was no indication of it whatever at Berlm, but the rank growth 
of vines and grasses because of generally poor cultivation was a fitting substitute. 

It is not intended to make any detailed comparison between the readings of the thermom- 
eters at Stations 3 and 5 at Berlin at corresponding positions, but to compare the readings 
at the surface at Station 3 with those at the 5-inch height at Station 5, the warmest and the 
coldest exposures on the bog. However, in Table S are fu'st given the readings of the mininnim 
thermometers at both the surface and 5 inches, and the differences between the readings at each 
station; and in the lower column, are given the differences between the readings at the surface 
at .Station 3 and the 5-inch height at Station 5. It is proper to state that the upper thermom- 
eter at Station 5 was not attached to any support, but was placed upon the vegetation which 
had been pressed down to a compact mass so that the thermometer rested 5 inches above the 
surface of the soil near the surface instruments. The lower thermometer was not shielded in 
the slightest degree by the upper one, but the radiation was freer at the higher elevation than 
from the lower thermometer which was obstructed laterally and obliquely by the dense vege- 
tation. At Station 3 the liigher thermometer was fastened to a post immediately above the 
thermometer which lay upon the ground. 

The average difference for the month between the surface thermometer at Station 3 and 
the upper thermometer at Station 5 was 10°, and the maximum daily difference was 17.1° on 
the 4th. On .only one day during the month was there an inversion of the usual conditions, 
September 2, and this was because there was water on tlie thermometers after a heavy rain. 
In fact, the readmgs of the instruments on that day should properly be excluded. These differ- 
ences in temperature at Berlin were even greater than those observed at Mather. 

The minimum thermometer in the shelter at Station 1 at Berlin, which was located on the 
edge of the bog, may be considered the standard as was that at Station 1 at Mather, and a 
comparison between the warmest and the coldest points on the bog at Berlin with this standard 
is important. For the month of September, 1906, the upper exposed thermometer at Station 5 
averaged 9.5° below that in the shelter at Station 1, while a maximum difference of 16.4° 
occurred on September 3, and on sixteen days there were differences exceeding 10°. (Table 
9.) In comparing the surface readings at Station 3 with the standard, it will be found that 
the exposetl minimum over the sanded section actually averaged for the month higher by 0.5°. 
It, moreover, was higher on eighteen days, whOe on tlu-ee days the readings were tlie same. 

These results indicate the great advantage gained in draining, cultivating, and sanding a bog. 
In spite of the fact that the thermometer at Station 3 urns exposed at the surface of the soil in the open 
where the radiation was perfectly free, it averaged higher than the one in the shelter on hard land. 
The conditions at Station 3 resemble approximately the improved conditions found in the 
Cape Cod marshes, while those at Station 5, on the other hand, are representative of the poorest 
conditions found in Wisconsin. It wouhl seem as a result of these observations that the Wis- 
consin growers should feel obligetl to adopt the Massachusetts methods. 



60 

Table 8.— Minimum Temperatures in the Open at Surface and at 5-Inch Height with Diffeminces, for 
Station 3, Heavily Sanded, Thinly Vined, and Station 5, Peat, Heavily Vined, Dense Groi^v^ op Vege- 
tation and Ferns, the Warmest and Coldest Parts of the Marsh, Respectively; Also Difference 
Between Surface, Station 3, and 5-Inch Height, Station 5, Berlin, Wis., September, 1900. 



Ii 





Station 3. 


Station 5. 


Difference- 
Station 3. 


Day of month. 


Surface. 


5 inches. 


Difference. 


Surface. 


5 Inches. 


Difference. 


surface, and 
Station 8, 
5 inches. 




o 


, 


o 


o 


o 


o 


o 


I 


51.5 


45.5 


-6.0 


40.2 


38.7 


-1.5 


-12.8 


, 


58.2 
52.0 


59.0 
43.5 


+0.S 
-8.5 


aes.o 

37.0 


35.0 


4-0.1 
-2.0 


+ 4-9 


3 - 


-17.0 


4 


51.0 
45.0 
52.0 
55.0 
56.8 


41.5 
35.9 

42.9 
50.0 

54.9 
60.0 
64. e 


-9.5 
-9.1 
-9.1 
-5.0 
-4.1 


37.5 
32.0 
39.8 
47.4 
49.0 


33.9 
28.3 
36.0 
44.0 
46.2 


-3.6 
-3.7 
-3.8 
-3.4 

-2.8 


-n.i 




-16.7 




-16.0 




-11.0 


8 


-10.6 


9 


59.0 
64.5 
68.0 


-4.1 
-4.5 

-1.4 


52.0 
56.0 
60.0 


49.7 
54.0 
60.7 


-2.3 
-2.0 
+0.7 


- 9.3 




-10.5 


11 


- 5.3 


12 


63.9 


59.5 


-4.4 


56.6 


54.8 


-1.8 


- 9.1 


13 


53.9 


52.8 


-1.1 


52.3 


50.8 


-1.5 


- 3.1 


14 


43.9 


35.0 


-8.9 


32.6 


28.8 


-S.S 


-15.1 


15 


48.1 


44.7 


-3.4 


42.8 


41.0 


-1.8 


- 7.1 


16 


56.0 


55.4 


-0.6 


53.9 


52.8 


-1.1 


- 3.2 


17 - 


62.3 


59.0 


-3.3 


56.0 


54.4 


-1.6 


- 7.9 


18 


64.0 


60.0 


-4.0 


55.8 


55.8 


0.0 


- S.2 


19 - 


60.0 


68.1 


-1.9 


52.9 


52.0 


-0.9 


- .8.0 


20 ■--■ 


60.0 


58.0 


-2.0 


58.0 


57.5 


-0.5 


- 2.5 


21 


60.0 


51.3 


-5.7 


50.9 


49.0 


-1.9 


-11.0 


22. 


55.1 
50.4 
41.0 


48.5 
45.0 
34.0 


-6.6 
-5.4 
-7.0 


45.8 

• 42.4 

31.8 


42.1 
38.9 
28.9 


-3.7 
-3.5 
-2.9 


-13.0 


23 


-11.5 


24 


-12.1 


25 


45.0 
54.8 


40.0 
53.8 


-5.0 
,-1.0 


38.0 
50.0 


34.3 
48.9 


-3.7 
-1.1 


-10.7 


26 - 


- 5.9 


27 ■ . 


40.3 
43.0 
54.3 
39. e 


SO.S 
35.7 
53.5 
31.0 


-9.5 
-8.3 
-0.8 
-8.6 


28.0 
31.5 
53.6 

sr.e 


24.4 
28.0 
53.6 
23.0 


-3.6 
-3.5 
-0.6 
-3.7 


-15.9 


28 


-15.0 


29 


- 1.3 


30. 


—16.6 






Means .. , . 


53.6 


48.7 


-4.9 


45.8 


43.6 


—2.2 


-10.0 







a Water on thermometers, and grass and vines very wet. due to rain. 
Highest and lowest readings are in italics. 



61 



Table 9. — Comparison of Minimum Temperatures in Shelter, Station 1, and in the Open at 5-inch Height 
AT Station 5, Peat and Heavily Vined, and at Surface at Station 3, Thinly Vined and Newly Sanded, 
Berlin, Wis., September, 1906. 



Day of month. 


Station 
1— Shel- 
ter. 


Station 

5-5 

inches 

exposed. 


Differ- 
ence. 


Station 
3— Sur- 
face ex- 
IMsed. 


Differ- 
ence — 
Stations 
1 and 3. 


Day of month. 


Station 
1— Shel- 
ter. 


Station 

5—5 

Inches 

exposed. 


Differ- 
ence. 


Station 
3— Sur- 
face ex- 
posed. 


Differ- 
ence- 
Stations 
1 and 3. 


1 


50.0 
65.7 
51.4 
46.8 
42.0 
47.6 
56.0 
57.4 
56.1 
64.5 
69.0 
62.9 
54.0 
41.3 
51.9 
57.9 


38.7 

"es.i 

35.0 
33.9 
28.3 
36.0 
44.0 
46.2 
49.7 
54.0 
60.7 
54.8 
50.8 
28.8 
41.0 
52.8 


-11.3 

- 2.6 
-16.4 
-12.9 
-13.7 
-11.6 
-12.0 
-11.2 

- 6.4 
-10.5 

- 8.3 

- 8.1 

- 3.2 
-12.5 
-10.9 

- 5.1 


51.5 
58.2 
52.0 
51.0 
46.0 
52.0 
55.0 
56.8 
59.0 
64.5 
66.0 
63.9 
53.9 
43.9 
48.1 
56.0 


-fl.5 
-7.5 
+0.6 
-1-4.2 
-fS.O 
+6.6 
-1.0 
-0.6 
+3.1 


-3.0 
-t-1.0 
-0.1 
-1-1.4 
-3.8 
-1.9 


17 


62.0 
64.0 
60.0 
5S.6 
59.0 
53.9 
50.3 
38.4 
47.0 
56.4 
S6.0 
41.1 
53.9 
38.0 


54.4 
55.8 
52.0 
57.5 
49.0 
42.1 
38.9 
28.9 
34.3 
48.9 
24.4 
28.0 
53.0 
SS.O 


- 7.6 

- 8.2 

- 8.0 

- 1.1 
-10.0 
-11.8 
-11.4 

- 9.5 
-12.7 

- 7.5 
-11.6 
-13.1 

- 0.9 
-15.0 


62.3 
64.0 
60.0 
60.0 
60.0 
55.1 
50.4 
41.0 
45.0 
54.8 
40.3 
43.0 
54.3 

S9.e 


-(-0.3 



9 


18 


3 


19 

20 

21..... 

22 

24. 

25 

20 

27 

28 

29 

30 

Means 





4 


-1-1.4 


5^ 


4-1.0 


6 


-1-1.2 


7... 


-1-0.1 


8 


-f3.4 


9 


-2.0 


10 


-1.6 


11 


-1-4.3 


12 


-t-1.9 


13 


-1-0.4 


14 


-1-1.6 








53.1 


43.6 


- 9.5 


53.6 




16 


-1-0.5 



a Water on thermometer, and grass and vines very wet, due to rain. 
Highest and lowest readings are in italics. 

Minimum temperatures over dry and moist sand, Stations 3 and 4. Berlin, Wis. — In order to 
further supplement the extensive observations made at Mather, a comparison was made between 
the surface ininimum thermometers at Berlin, at Stations 3 and 4, tlry and wet sand, for Septem- 
ber, 1906. This comparison was made because data of the kind desired were not available at 
Mather, the sanded sections there being all comparatively dry. Both these stations were located 
in the thinly vined section, and there w^as apparently no difl'erence in the character of the two 
stations, except that one was much wetter than the other. (See Table 10.) The temperature 
at the surface at Station 4 averaged 2.4° lower than that at the surface at Station 3, and there 
was an extreme difference* of 7.3° on September 30, when the thermometer at Station 3 regis- 
tered 39.6°, and the one at Station 4, 32.3°. On the folloiving day, October 1 (not included in 
this table), the minimum at Station 3 registered 35.8°, and at Station 4, 27.3°, the difference being 
8.5°. It was on this date that the berries were frozen generally in the bog except in the dry sanded 
section. On only one tlay did the thermometer at Station 3 register lower than the one at 
Station 4. The increased amount of moisture at Station 4 is solely responsible for the rela- 
tively low temperature readings, on account of the heat lost in the evaporation at the surface. 
Wliile the reading of 64° on September 2 is included in the table and in the averages, it is not 
consistent with the other readings, and was due to w'ater on the bulb of the instrument after a 
heavy rain. 

Table 10. — Minimum Temperatures in the Open at Surfaces of Stations 3 and 4, with Differences, Berlin 

Wis., September, 1906. 



Day of month. 



3- 

4. 

5. 

6. 

7. 

8. 

9. 
10. 
11.. 



Station 


Station 


Differ- 


3. 


4. 


ence. 


. 


i 


. 


51.5 


47.8 


-3.7 


58.2 


O64.0 


-1-5. « 


52.0 


48.0 


-4.0 


51.0 


48.0 


-3.0 


45.0 


43.2 


-1.8 


52.0 


48.1 


-3.9 


55.0 


52.1 


-2.9 


56.8 


56.0 


-0.8 


59.2 


59.4 


4-0.2 


64.5 


64.3 


-0.2 


66.0 


66.0 


-1.0 



Day of month. 


Station 
3. 


12 


63.9 
53.9 
43.9 
48.1 
56.0 
62.3 
64.0 
60.0 
60.0 


13 


14 


15 


16 


17 


18 


19 


20 


21 


60.0 


22 


55.1 







Station 
4. 



62.1 
53.0 
37.7 
47.0 
56.5 
60.8 
63.0 
57.9 
59.0 
.56.1 
51.3 



Differ- 
ence. 



-1.8 
-0.9 
-6.2 
-1.1 
-1-0.5 
-1.5 
-1.0 
-2.1 
-1.0 
-3.9 
-3.8 



Day of month. 



Means . 



Station 
3. 


Station 
4. 


o 


o 


50.4 


47.1 


41.0 


37.4 


45.0 


42.7 


54.8 


52.8 


40.3 


33.1 


43.0 


38.0 


54.3 


53.4 


S9.6 


SB.S 


53.6 


51.2 



Differ- 
ence. 



-3.3 
-3.6 
-2.3 
-2.0 
-7.2 
-5.0 
-0.9 
-7.S 



a Water on thermometer, and grass and vines very wet, due to rain. 
Both stations thinly vined and lieavily sanded, but Station 3, dry sand, and Station 4, wet sand. 

Highest and lowest readings are in italics. 



62 

Minimum temperatures over peat hogs, heavily rined and thinly inned, Berlin, Wis., ^eptemher, 
jgog^ — In Tables 8 and 9 appear the readings of exposed minimum tliermometers located at 
Station 5, in the ferns at Berhn, the coldest point in the Berlin bog. As stated above, the vegeta- 
tion was verj- rank there. Station 2 at Berlin resembled Station 5 in its peat soil and want 
of good drainage, but it had in the sprng of 1906 been thoroughly weeded, so that the vege- 
tation was thin. Stations 2 and .5, then, ma}' therefore well represent respectively thinly 
vined and densely vined locations. The record of the exposed mininnims for September, 1906, 
ab an elevation of 5 inches above the surface. Table 11, shows that Station 5 averaged .3.4° 
lower than Station 2. A maximum dilTerence of 6.6° occurred on September 27, and if we 
exclude the readings of September 2, when water was on the bulb of the thermometer at Station 
5, after a heavy rain, there is not a single instance in which the minimum at Station 2 was lower 
than the one at Station 5. The great differences in temperature are due entirely to weeding, 
the soil in the thinly vined section during the growing season being much warmer than a soil 
covered with dense vegetation. Radiation, however, should be just as free from a thinly lined 
peat soil as from one heavily vined. 

It is as important to cidtivate as it is to practice drainage. Of course it is impossible 
to determine absolutely the advantage in exact degrees gained by cultivation, draining, or 
sanding. While there is an average difference of 3.4°, as shown by Table 11, between the 
minimum thermometers in the thinly vined and the heavily vined .sections, a difference of 
2.4°, as shown by Table 10, between the minimum thermometers on wet and on ilrv sand, a 
difference of 1.7° between thermometers on peat and sanded bogs, both thinly vined, and a 
difference of 2.2° 'between the surface and 5 inches, it is obvious mIiv an average difference of 
10°, as shown by Table S, can exist between a minimum thermometer exposed at the most 
favorable location as far os drainage, samling, and cultivating are concerned, and another in a 
most unfavorable location, an unsanded peat section with a very dense growth of vegetation, 
and poor drainage. It is not strange, therefore, that in a bog where there is a variation in tiie 
conditions of sanding, draining, and cultivation, the range in minimum temperature is con- 
siderable, and that a portion of a bog is .seriously injured by frost, while another portion com- 
pletely escapes. It should be apparent why the experiment station at Cranmoor, Wis., wliere 
intensive cranberry growing is practiced, does not require reffowing of its bog on many cold 
nights in order to escape injury, when the crop of an unimproved liog might be completely 
wiped out unless protected b_y reflowing. For the same reason, the Cape Cod growers, on account 
of the excellent condition of their marshes, are seldom forced to use water for protection except 
in the late autumn. 

T.\Bi.E 11, — MiN'i.MUM Temperatures in the Open at 5-inch Height, at Stations 2 and .5, with Difference.s 

Berlin, Wis., September, 1906. 



Day of month. 


Station 
2—5- 
inch. 


Station 
5—3- 
inch. 


Differ- 
ence. 


1 


41.fi 
59.3 
39.5 
38.9 
33.1 
40.8 
47. B 
50.0 
52.4 
57.4 
64.0 


38.7 
1^63.1 
35.0 
33.9 
28.3 
30.0 
44.0 
40.2 
49.7 
54.0 
60.7 


-2,9 
-1-3. S 
-4.5 
-5.0 
-4.8 
-4.8 
-3.6 
-3.8 
-2,7 
-3.4 
-3.3 


2 


3 


4 


5 


6 


7 


8 


9 


10 


11 





Station 
Day of month. I 2 — 5- 
inch. 



12. 
13, 
14. 
15, 
10, 
17. 
18, 
19 
20 
21 
22 



57.4 
53.0 
33.0 
44.5 
54.9 
57.3 
57,6 
58,0 
58.0 
51.4 
47,0 



Station 

5—5- 
inch. 



54.8 
50.8 
28.8 
41.0 
52.8 
54.4 
55.8 
52.0 
57.5 
49.0 
42.1 



Differ- 
ence. 



-2.6 
-2.2 
-4.2 
-3,5 
-2.1 
-2.9 
-1.8 
-6.0 
-0.5 
-2.4 
-4.9 



Day of month. 



23 

24 

23 

26 

27 

28 

29 

30 

Means 



Station 

2—5- 
inch. 



Station 
5—5- 
inch. 



43.8 
32.5 
38,7 
52.8 I 
31.0 
31.9 
53,0 i 
28.8 j 

47.0 



38.9 
28.9 
34,3 
48.9 
24.4 
28.0 
53.0 
23.0 

43.6 



Differ- 
ence. 



-4.9 
-3.6 
-4.4 
-.3.9 
-«.« 
-3.9 
-0,6 
-5,8 



o Water on thermometer, and grass and vines very wet, due to rain. 

Station 2. Peat bog, thinly vined. 

Station 5. Peat bog, heavily vined, with dense growth of vegetation and ferns. 

Highest and lowest readings are in italics. 



63 

Minimum temperatures over peat hog and sanded hog, thermometers exposed at 5 inches ahove 
the surface, at Cranmoor, Mather, and Berlin. — Having made a comparison between the exposed 
minimums in various portions of the same bog at both Mather and Berhn, it is interesting 
to note how the readings vary in different bogs, for the season or a portion of the season, 
when the minimum thermometers are exposed in the vines over different soils at the height 
of 5 inches above the surface. In Table 12 we have a comparison between Cranmoor," Mather, 
and Berlin for the months of August and September, 1906, at certain selected stations over 
peat and sanded bogs. The locations in each marsh were respectively the coldest and the 
warmest points, although it should be understood that the exposures of the thermometers 
given were at an elevation of 5 inches above the ground, the minimums, of course, registering 
higher at the surface where the radiation was less free. The sanded surfaces at the three 
stations closely resembled each other, while the exposures in the peat bog were over moss at 
Cranmoor and Mather and in the ferns at Berlm, there being no moss at the latter station. 
The vegetation was dense, however, in all three peat bogs, it being densest at Berlin. The 
average daily and the average monthly readings at any particular station are in themselves 
of little consequence in the discussion of Table 12, as there may be a variation in temperature 
because of the difference in geographical location. The average readings at corresponding 
locations at Cranmoor, Mather, and Berlin for the two months did not vary materially, but it 
is M'ith the differences between the exposed minimums over the peat antl the sanded bogs in 
which we are especially interested. For the two months the temperature over the sanded bog 
averaged higher than over the peat, as follows: Cramnoor, 5.3°, Mather, 4.4°, and Berlin 5.4°; 
the greatest daily difference was 11° at Cranmoor on August 30 and at Mather on September 15, 
and 19° at Berlin on August 11. At no time did the minimum over the peat register higher 
than that over the sand at any one of the three stations, with the single exception of September 
2 at Berlin, when the instrument in the peat bog was affected by water, after a heavy rain. 
There were several dates, however, invariably on cloudy nights, when there M-as no difference 
between the readings of the instruments over the peat and the sand; but, of course, on these 
nights the temperature was high and there was no danger from frost. 

In 1907 and 1908 data are available for the season at Cranmoor and Mather only, the 
Berlin station having been discontinued. It did not seem necessary to publish the tables 
for these two years. The most important features, however, were as follows: At Cranmoor 
in 1907 the differences averaged greatest during the summer months of July and August, 6.7° 
and 6.6°, respectively, while at Mather the greatest average monthly difference was 4.2° in 
September, this being 0.1° higher than the average for August. The greatest difference at 
Cranmoor on any one day was 12° on June 27, while the greatest ilifference at Mather was 8° 
on September 2 and 3 and October 5. In 1908 the average difference was 4.5° at Cranmoor and 
4° at Mather, and the greatest difference on any one day occurred on August 5, 1 1 ° at Cranmoor, 
and at Mather the greatest difference, 8°, occurred on seven different days. 

" Observations over sanded bog made at Cranmoor Experiment Station and those over peat af the Gaynor- 
Blackstone marsh immediately adjoining. 

51936"— Bull. T— 10 5 



64 

Table 12.— Minimum Temperatures in Open over Peat Bog with Dense Vegetation, and in "&nes over 
Sanded Bog, both at the Height of 5 Inches, the Latter Representing Best Results from Sanding, 
Draining, and Cultivating at Cranmoor. Mather, and Berlin, Wis., August and September, 1906. 



[P. indicates peat bog; 


S. indicates sanded surface; Diff. indicates e.xcess of temperature of sanded surface 


over that of the peat bog.; 












August, 1906. 








September, 1906. 


Day of month. 


Craamoor. 


Mather. 


Berlin. 


Cranmoor. 


Mather. 




Berlin. 






P. 


S. 


DifF. 


P. 


S. 


Difl. 


P. 


S. 


Difl. 


P. 


S. 


Difl. 


P. 


S. Diff. 


P. 


S. 


Dill. 


1 


47 
53 
55 
48 
65 
46 
59 
57 
63 
55 
46 
47 
43 
46 
45 
50 
55 
59 
60 
59 
64 
64 
64 
69 
68 
65 
33 
35 
44 
SO 
34 


54 
55 
61 
56 
65 
53 
60 
64 
65 
62 
54 
50 
52 
54 
53 
57 
60 
61 
64 
65 
68 
67 
68 
60 
68 
67 
S8 
42 
52 
41 
44 


+ 7 
+ 2 
+ 6 
+ 8 


+ 7 
+ 1 
+ 7 
+ 2 
+ 7 
+ 8 
+ 3 
+ 9 
+ 8 
+ 8 
+ 7 
+ 5 
+ 2 
+ 4 
+ 6 
+ 4 
+ 3 
+ 4 
+ I 


+ 2 
+ 5 
+ 7 
+ 8 
+11 
+10 


55 
55 
55 
48 
64 
48 
58 
59 
64 
60 
51 
44 
47 
48 
45 
51 
54 
55 
58 
63 
64 
64 

6e 

60 
61 
62 
SI 
34 
52 
36 
36 


57 
57 
59 
54 
64 
53 
60 
62 
66 
64 
57 
49 
52 
53 
50 
56 
59 
60 
62 
67 
68 
67 
69 
60 
69 
63 
a 40 
ii42 
56 
42 
42 


+ 2 
+ 2 
+ 4 
+ 6 


+ 5 
+ 2 
+ 3 
+ 2 
+ 4 
+ 6 
+ 5 
+ 5 
+ 5 
+ 5 
+ 5 
+ 5 
+ 5 
+ 4 
+ 4 
+ 4 
+ 3 
+ 4 


+ 4 
+ 1 
+ 9 
+ 8 
+ 4 
+ 6 
+ 6 


45 
52 
57 
50 
66 
41 
56 
60 
61 
55 
48 
45 
39 
44 
44 
49 
62 
54 
58 
64 
65 
60 
61 
60 
66 
68 
SO 
36 
48 
36 
38 


56 
56 
63 
52 
66 
54 
62 
64 
64 
63 
67 
61 
45 
50 
50 
57 
65 
58 
58 
69 
70 
64 
61 
61 
67 
68 
S8 
44 
52 
46 
44 


+11 
+ 4 
+ 6 
+ 2 


+13 
+ 6 
+ 4 
+ 3 
+ 8 
+19 
+16 
+ 6 
+ 6 
+ 
+ 8 
+ 3 
+ 4 


+ 5 
+ 5 
+ 4 


+ 1 
+ 1 


+ 8 
+ 8 
+ 4 
+10 
+ 6 


38 
61 
32 
35 
32 
37 
42 
47 
47 
53 
58 
60 
49 
28 
47 
59 
58 
58 
56 
54 
52 
41 
37 
34 
35 
40 
26 
26 
51 
17 


o. o 

46 , + 8 
61 1 
43 . +11 
42+7 


38 
55 
35 
36 
33 
36 
44 
47 
48 
56 
6S 
60 
48 
31 
40 
58 
57 
58 
50 
54 
49 
44 
41 
38 
38 
40 
28 
31 
36 
BS 


44 
64 
43 
40 
40 
42 
49 
53 
53 
60 
66 
61 
49 
34 
51 
65 
60 
62 
56 
55 
55 
49 
46 
42 
43 
42 
34 
36 
39 
B8 


+ 6 
+ 9 
+ 8 
+ 4 
+ 7 
+ 6 
+ 5 
+ 6 
+ 5 
+ 4 
+ 2 
+ 1 
+ 1 
+ 3 
+11 
+ 1 
+ 3 
+ 4 
+ 6 
+ / 
+ 6 
+ 5 
+ 5 
+ 4 
+ 5 
+ 2 
+ 6 
+ 5 
+ 3 
+ 3 


o 

39 
6S 
35 
34 
28 
36 
44 
46 
50 
54 
61 
55 
51 
29 
41 
53 
54 
56 
52 
58 
49 
42 
39 
29 
34 
49 
24 
28 
53 
BS 


e 

46 
59 
43 
41 
36 
43 
50 
53 
55 
60 
66 
60 
53 
35 
45 
55 
59 
60 
58 
58 
54 
48 
45 
34 
40 
54 
SI 
36 
54 
SI 


+ 7 


2 


- 1, 


3 


+ 8 


4 '. . 


+ 7 


5 


41 
45 
50 
52 
54 
60 
6S 
6S 
51 
36 
49 
59 
61 
6S 
57 
55 
56 
49 
45 
42 
42 
43 
33 
33 
54 
S9 


+ 9 

+ 8 
+ 8 
+ 5 
+ 7 
+ 7 
+ 4 
+ 2 
+ 2 
+ 8 
+ 2 

+ 3 
+ 4 
+ 1 
+ 1 
+ 4 
+ 8 
+ 8 
+ 8 
+ 7 
+ 3 
+ 7 
+ 7 
+ 3 
+12 


+ 8 





+ 7 


7 : 


+ 6 


8 


+ 7 


9 


+ 5 


10 


+ 6 


11 


+ 4 


12 


+ 5 


13 


+ 2 


14 


+ 6 


15 


+ 4 


Ifi ' ■.. 


+ 2 


17 


+ 5 


18 

19 

20 - 

21 

22 


+ 4 
+ 6 

+ 5 
+ fl 


23 


+ 6 


24 


+ 5 


25 


+ 6 


20 


+ 5 


27 


+ 7 


28 . . . 


+ 8 


29 


+ 1 


,30 


+ « 


31 
























Means 


52.2 


57.4 


+5.2 


53.3 


57.3 


+4.0 


52.2 


57.9 


+5.7 


43.7 


49.1 


+5.4 


43.9 


48.7 +4.8 


43.6 


48.7 


+5.1 



a Water on thermometer, from rain. 
Highest and lowest readings are in italics. 

Table 12a. — Means of Table 12. 



Cranmoor: 

Peat bog . 



Sanded surface.. 
Difference , 

Mather: 

Peat bog 

Sanded surface . 
Difference 

Berlin: 

Peat bog 

Sanded surface- 
Difference 



Means. 




65 

Readings of exposed minimurns at various elevations over hog and upland , Stations 2 arul 9, 
Mather, Wis. — In the preceding pages there have been discussed the variations in temperature 
at various locations at the surface and at the height of 5 inches, and the connection existing 
between these temperatures and the temperature of the soil at the point of exposure. Excepting 
the minimum thermometers that were exposed in the shelters at Stations 1 at both Mather 
and Berlin, no reference has previously been made in this paper to the reading of an instrument 
higher than 5 inches above the surface. 

In order to supplement the comparison of exposed minimum thermometers at the surface 
and 5 inches above, readings were made at Mather of instruments at Stations 2 and 9 placed as 
follows: Surface, 2i inches, 5 inches, 7h inches, 10 inches, 12 inches, 15 inches, and 36 inches 
above the surface. The character of these stations of course differs radically. Station 2 being 
located in the bog over sphagnum moss, while Station 9 was in the garden on the upland where 
the surface was comparatively clean antl the soil a sandy loam. The difference in elevation 
between the two stations is about 15 feet. The results would have answered the purpose 
better had both the stations selected for this comparison been located on the bog. Daily, 
monthly, and seasonal averages appear m Tables 13, 13a, 14, 14a. 

At Station 2 the minimum temperature averaged lowest for the entire season at the 5-inch 
height, the average being 40.1°. The temperature gradually increased thence upward and do\vn- 
ward, being 41.8° at the surface and 43.2° at the 36-inch height, the surface reading therefore 
averagmg 1.7° higher than at 5 inches and 1.4° lower than at 36 inches. In every month the 
average temperature was highest at 36 inches, with a secondary maximum at the surface. In 
May and June the temperature averaged slightly lower at 24 niches than at 5 inches. For 
the entire season the temperature at 5 inches averaged onl}' 0.2° below that at 24 inches. 

At Station 9 on the upland the average difference between the thermometers was not so 
great. The temperature at 24 inches averaged lowest, 44.5°, instead of at 5 inches, as on the 
bog, but the difference was very slight between these two elevations — 0.1°. The surface ther- 
mometer averaged highest, 45.5°, but there was only 1° difference on an average between the 
two extremes, while the average surface reading was 0.6° higher than at 36 inches. The 
average for the entire season fairly represents the conditions prevailing each month, the highest 
in each case occurring at the surface and the lowest at 24 inches. 

While at Station 2 the minimum thermometer was usually the lowest at either 24 inches 
or 5 inches above the surface, and the temperature averaged higher for each month and the 
season at 36 inches than at the surface, yet on clear, cool nights, when radiation was the freest, 
the exposed minimum at 36 inches usually registered lower than at the surface. Moreover, on 
the coolest nights the difference between the exposed minimum at the surface and the 5-inch 
height was the greatest, occasional^ exceeding 6°, as in October. (See Table 2.) On warm 
nights, however, almost without exception, the temperature at 36 inches registered consider- 
ably higher than at the surface, the maximum difference occurring on June 17, 6.7°, a partly 
cloudy night. On that date the surface thermometer was 62.1°, the one at 36 inches 68.8°, 
and at 5 inches 62.9°, this reading being higher than at the surface, and the lowest reading 
occurring at 2J inches, 62°. At Station 9, of course, the variation was not so great, but it is 
interesting to note that while the average temperature at this station at the surface was higher 
than at 36 inches, and this fact was most pronounced on cold, clear nights, nevertheless, on 
warm nights the reverse was the case, the temperature at 36 inches almost invariably being 
higher than at the surface ; or, in other words, at both stations, on clear, cool nights the ther- 
mometers at the 36-inch height usually registered lower than at the surface, and on warm 
nights the thermometers at 36 inches usually registered higher than at the surface, it being 
understood, however, that on both cool and warm nights the lowest temperature at both Stations 
2 and 9 occurred neither at the surface nor at 36 inches, but at some point between the two, 
usually at 2^ or 5 inches. 

On June 17, referred to above, when at Station 2 the surface thermometer registered 
62.1°, and at 36 mches 68.8°, the readmgs at similar exposures at Station 9 were 67.1° and 



66 

67.3°, respectirety, the upper thermometer at Station 2 on the bog actually reading higlier 
by 1.5° than the one at Station 9 on the upland. On August 10, when the surface instruments 
at Stations 2 and 9 registered, respectively, 52.6° and 53.1°, the readings at 36 inches were, 
respectively, 57.8° and 51 .8°, the one on the bog therefore registering 6° higher than the one 
on the upland. 

It is important to note that at both Stations 2 and 9 there is an al)rupt change in tempera- 
ture between the surface and 2^ inches, the readings of the surface instruments being kept up 
by the conduction of heat from the ground, although unequally. Above 2h inches the change 
at Station 9 is gradual. The average difference between the readings at 15 inches and 36 
inches was only 0.1°, while at Station 2 on the bog the difference was 2.1°. Moreover, at Station 
2 the average range for tlie season was 3.1°, from the minimum of 40.1° at 5 inches to the maxi- 
mum of 43.2° at 36 inches. At Station 9 the average range for similar exposures was onl}' 
0.3°, from a minimum of 44.6° at 5 inches to a maximum of 44.9° at 36 inches. However, the 
extremes at Station 9, as has been stated before, were at the surface and 2i inches, 45.5° and 44.5°, 
respectivel}', the range being but 1°. Where the minimum thermometers were placed directly 
one above another, as at Stations 2 and 9, it is obvious that tlie thermometer at 2^ inches is 
shielded as much by the six thermometers above as the one at the surface by the seven ther- 
mometers; but, nevertheless, the radiation amidst vegetation should be freer as the elevation 
increases. The lower down the thermometers are the more the radiation from them is interfered 
with, laterally and oblicjuely, by the surrounding vegetation. A thermometer or leaf elevated 
above the ground loses its heat more rapidly than if it rests upon the surface, because in the 
former case there is likely to be freer radiation in all directiojis; moreover, the heat conducted from 
the soil beneath affects the thermometer or leaf resting ujion tlie surface and prevents its tem- 
perature from falling as low as it would if located a few inches above. Of course colder air, 
being heavier, gradually sinks to lower levels, but this process is very slow, while the processes of 
radiation and conduction may continue active. The problem is a complicated one, as man}' 
factors are involved, such as liumidity, wind velocitj'', condition of the sky, barometric pressure, 
length of night, general temperature conditions, the temperature and composition of the soil, and 
its moisture and the character of its covering. It is cpiite difficult, however, to explain why 
the exposed minimum was almost uniformly lower at a few inches above the surface, except on 
the theory that the surface thermometer receives heat from the soil beneath. In any case, 
these results are important, as they show approximately the variation in minimum temperature 
to which vegetation in the bogs is subjected. 



67 

Table 13. — Minimum Tempkratures in Open at all Elevations at Station 2, Over Sphagnum Moss on the 

Marsh, Mather, Wis., 1007. 











May." 








June. 


]iay of month. 


Sur- 
face. 


2i 
nches. 


5 
inches. 


7J 
inches. 


ID ! 
nches. 


12 
inches. 


15 
inches. 


36 
nches. 


Sur- 
face. 


2J 
nches. 


5 
nches. 


7J 
nches. 


10 
nches. 


12 
inches. 


15 
inches. 


36 
inches. 


I 


• 


' 


• 


- 


• 


o 


• 


= 


30.3 
30.4 
50.0 
36.0 
36.7 
SO.l 
43.0 
30.2 
34.3 
52.0 
40.2 
50.9 
35.0 
32.3 
37.0 
47.8 
63.1 
51.0 
48.0 
43.8 
43.0 
59.8 
55.0 
50.6 
54.6 
42.4 
38.0 
39.6 
44.8 
51.0 


S7.S 
29.6 
52.2 
35.4 
37.6 
28.0 
44.0 
28.0 
32.8 
53.0 
38.9 
50.4 
34.4 
31.4 
35.0 
46.0 

etc 

49.5 
46.5 
42.3 
41.5 
58.5 
53.7 
49.4 
52.9 
41.0 
35.8 
36.8 
42.5 
48.9 


n.9 

29.4 
53.0 
35.2 
38.0 
17.9 
44.8 
27.9 
32.9 
53.3 
39.1 
50.5 
34.4 
31.0 
35.0 
46.0 
62.9 
49.6 
46.8 
42.3 
41.4 
59.0 
53.9 
49.6 
53.0 
40.9 
35.2 
36.7 
42.6 
48.9 


28.0 
29.8 
53.0 
35.3 
38.8 
18. 
45.0 
28.1 
32.8 
53.1 
39.5 
50.5 
34.7 
31.1 
35.0 
46.1 
6S.9 
49.8 
47.0 
42.2 
41.4 
59.2 
54.0 
49.9 
53.0 
41.1 
35.4 
36.8 
42.8 
49.0 


o 

28.8 
29.8 
53.0 
35.9 
39.1 
SS.O 
45.3 
28.5 
33.0 
53.0 
39.8 
50.5 
35.0 
31.1 
35.3 
46.1 
65.0 
49.8 
47.4 
42.5 
41.6 
59.5 
54.1 
50.0 
53.1 
41.8 
35.9 
37.0 
43.0 
49.0 


28.3 
29.0 
52.8 
35.5 
38.9 
27.9 
45.0 
28.0 
32.8 
52.8 
40.0 
50.4 
35.9 
31.0 
35.3 
46.0 
65. S 
49.8 
47.5 
42.5 
41.5 
59.5 
54.1 
50.1 
53.4 
42 1 
36.0 
37.0 
43.0 
49.0 


28.8 
30.1 
53.8 
36.4 
40.0 
28.9 
46.0 
29.0 
33.9 
53.8 
41.1 
50.2 
36.0 
32.0 
36.1 
47.0 
66.8 
50.6 
48.9 
43.1 
42.0 
60.0 
55.1 
51.0 
54.0 
43.1 
36.5 
37.3 
43.7 
50.6 


32.3 


















32.8 


3 
















54.0 


















38.0 


5 


















40.9 


6 


















29.3 





















46.5 


s 
















30.8 


















36.0 


10 
















53.8 


n 


















43.8 


12 


32.5 

et.o 

45.9 
37.5 
34.3 
32.8 
32.8 
29.8 
SO. 9 
23.9 
41.0 
44.0 
36.9 
44.8 
45.5 
29.4 
29.2 
30.6 
36.8 
4(.'.8 


34.9 
59. S 
45.0 
38.5 
34.0 
32.0 
31.6 
28.1 
18.0 
20.9 
43.1 
43.8 
38.4 
44.0 
45.3 
27.0 
27.4 
29.4 
35.9 
45.3 


35.2 
60. 
44.5 
36.3 
34.1 
32.4 
32.0 
28.2 
18.0 
21.0 
44.0 
43.9 
40.2 
44.0 
45.2 
27.0 
27.3 
29.8 
36.0 
45.0 


35.4 
60. S 
44.9 
36.0 
34.0 
33.0 
33.0 
28.3 
18. S 
21.0 
44.0 
43.9 
41.0 
44.0 
45.0 
27.4 
27.9 
30.0 
36.6 
45.0 


35.9 
60. 
44.9 
36.0 
34.0 
34.0 
34.0 
29.1 
18.9 
21.2 
44.0 
43.9 
41.3 
44.0 
45.0 
27.8 
28.0 
30.5 
36.9 
45.1 


34.7 
S9.S 
43.9 
35.0 
33.0 
33.4 
33.9 
28.6 
18.0 
20.6 
43.0 
42.9 
40.8 
43.0 
44.2 
27.0 
27.4 
30.1 
36.3 
44.8 


35.0 

eg.s 

44.0 
35.1 
34.9 
34.3 
35.1 
29.3 
18 S 
20.5 
43.0 
43.0 
41.9 
43.0 
44.0 
27.3 
27.8 
30.5 
36.4 
43.8 


36.1 
61.0 
44.8 
35.7 
34.1 
37.4 
39.5 
33.3 
W.$ 
22.1 
44.0 
44.0 
42.3 
43.7 
45.0 
29.0 
32.4 
35.2 
40.9 
45.6 


51.9 


13 


39.3 


14 


35.0 


15 


37.8 


16 


49.2 


17 


68.8 


18 


.53.8 


19 


51.0 


20 


45.5 


21 


44.0 


22 


60.7 


23 


57.8 


24 


53.2 


25 


55.3 


26 


44.5 


27 


38.6 


28 


39.0 


29 


46.7 


30. 


53.1 
















1 








31). 8 


36.0 


36.2 


36.4 


36.7 


36.0 


36.3 


38.8 


43.3 


42.2 


42.3 


42.5 


42.7 


42.7 


43.5 


45.4 







a Means for twenty days. 
Highest and lowest readings are in italics. 



68 

Table 1.!. — JIiximum Temperatures in Open at all Elevations at Station 2, Over Sphacnum Moss on the 

Marsh, Mather, Wis., 1907 — Continued. 



Dav of month. 



10. 
11. 
12. 
13. 
14. 
15. 
16. 
17. 
IS. 
IS). 
20. 
21. 
22. 
23. 
24. 
25. 
2B. 
27. 
28. 
29. 
30. 
31. 



July. 



Sur- 
face. 



54.0 
SS.l 
38.5 
47.2 
59.0 
56.1 
47.8 
50.9 
55.0 
46.7 
62.9 
46.2 
48.8 
59.9 
67.1 
50.3 
48.0 
47.5 
54.8 
53.7 
63.4 
60.2 
49.1 
O60.3 
48.9 
45.3 
44.4 
59.0 
52.0 
49.0 
53.0 



52.0 



2% 5 

inches. Inches 



51.6 
«9.9 
38.6 
44.4 
59.0 
52.6 
43.7 
47.6 
51.4 
42.8 
60.7 
42.2 
44.6 
56.6 
67.4 
46.6 
45.1 
45.0 
52.0 
50.2 
60.5 
57.0 
50.2 
59.0 
51.1 
42.8 
41.3 
55.0 
48.2 
46.1 
42.9 



49.2 



52.0 
«9.4 
38.5 
44.7 
59.4 
52.8 
43.3 
47.0 
51.0 
42.3 
60.2 
42.3 
44.6 
66.4 
67.8 
46.3 
45.0 
44.5 
51.8 
50.0 
60.2 
57.3 
48.9 
58. 7 
49.5 
42.3 
41.0 
56.3 
48.1 
46.0 
48.5 



49.2 



inches 



38.7 
44.7 
59.5 
52.9 
43.8 
47.7 
51.0 
42.5 
59.9 
42.1 
44.8 
56.7 
67.9 
46.4 
45.1 
43.9 
51.9 
50.3 
60.1 
57.4 
49.0 
58.8 
49.3 
42.4 
40.6 
55.4 
48.1 
44.9 
48.5 



49.2 



10 
inches. 



12 
inches. 



54.3 
29.8 
38.9 
44.8 
60.0 
53.0 
44.0 
47.8 
61.3 
42.8 
60.0 
42.0 
44.7 
67.0 
68.0 
46.6 
48.2 
44.0 
52.0 
50.5 
60.0 
57.9 
48.7 
58.8 
49.2 
42.5 
40.6 
55.7 
48.0 
44.6 
48.4 



49 4 



54.9 
29.7 
39.0 
44.9 
60.0 
53.0 
44.0 
48.0 
51.7 
43.0 
60.0 
42.1 
44.8 
57.5 
68. 
46.7 
45.7 
44.2 
52.0 
51.0 
60.2 
58.5 
48.8 
58.9 
49.4 
42.8 
40.8 
56.0 
48.1 
44.4 
48.6 



49.6 



15 
inches. 



55.9 
SO.O 
39.8 
45.0 
60.5 
54.8 
44.3 
49.0 
62.2 
43.2 
60.0 
42.4 
45.2 
58.4 
68.1 
47.0 
46.4 
44.6 
52.5 
52.0 
61.0 
59.4 
49.1 
59.7 
50.0 
43.0 
41.0 
66.5 
49.0 
44.5 
48.9 



50.1 



36 
inches. 



56.4 
Sl.i 
42.1 
46.9 
60.5 
56.0 
46.2 
53.0 
55.7 
46.0 
60.1 
45,1 
48.8 
60.5 
68 S 
48.2 
50.0 
46.0 
54.5 
65.0 
62.9 
61.7 
60.0 
61.7 
50.9 
45.0 
42.2 
58.5 
52.0 
47.9 
51.0 



52.1 



August. 



Sur- 
face. 



61.3 
44.4 
43.0 
35.9 
68.0 
49.4 
51.0 
54.2 
52.0 
52.6 
70.0 
44.9 
45.0 
48.8 
51.9 
59.6 
46.4 
50.2 
64.7 
38.0 
39.5 
S5.6 
50.0 
44.0 
35.9 
45.0 
57.0 
51.4 
46,0 
62.6 
53.5 



5 
inches. 



49.4 



47.7 
40.0 
40.5 
34.6 
58.0 
46.8 
48.7 
51.6 
49.0 
54.5 
70.0 
40.3 
42.2 
46.2 
49.7 
57.7 
43.6 
47.7 
64.7 
34, C 
36,2 
34.6 
47.6 
41.6 
SS.2 
42.8 
57.0 
50.0 
44.5 
62.5 
52.5 



47.4 



47.0 
39.1 
40.0 
34.1 
57.9 
46.0 
48.2 
51.0 
48.9 
54.6 
70.5 
40.1 
42.0 
46.0 
49.6 
57.7 
43.4 
47.7 
64.7 
34.1 
35.7 
33.9 
47.2 
41.0 
SS.7 
42.5 
56.6 
49,9 
43.7 
62.3 
62.4 



incties. 



47.1 



47.0 
39.4 
40.1 
SS.2 
58,0 
46.0 
48.1 
51.0 
49,2 
54,5 
70.8 
40.1 
42.6 
46.5 
60.0 
58.2 
43.8 
47,9 
64.9 
34.7 
36.5 
34.6 
48,0 
41,7 
34,0 
43,4 
67,0 
50,7 
44.6 
62.7 
52.7 



10 I 12 15 

inches, inches, inches. 



47.5 



46.9 
39.5 
40.3 
SS.t 
68,0 
46,0 
48,2 
50,5 
49,0 
64,5 
71,0 
40,0 
42,3 
46,4 
49,7 
57,8 
43,6 
47,6 
64,6 
34,6 
36,3 
34,2 
47,6 
41.5 
34.0 
43.4 
56.5 
50.6 
44,6 
62,6 
52,7 



47,3 



46,9 
39.7 
40.4 
SS.S 
58,0 
46,1 
48,5 
50,8 
49,4 
54,9 
7/,0 
40,3 
42.5 
46.5 
50.0 
57.9 
43.6 
47.7 
64.7 
34.3 
36.4 
34,3 
47,7 
41,8 
34,6 
43,6 
56,4 
50,9 
44,8 
62,7 
53.0 



47.0 
39.9 
40.6 
S3. 4 
58.0 
46.2 
49.3 
50.9 
49.6 
54.4 
70.9 
40,3 
42.5 
46.2 
51.6 
57.9 
46.1 
48.0 
64,8 
35.0 
36.6 
34,5 
48.0 
42.5 
35.0 
43.9 
56.7 
51.0 
44.9 
62.6 
53.5 



inches. 



47, 5 47, 8 



49.7 
42.0 
42,9 
SB. 4 
58.4 
49.0 
53.0 
53.4 
52.0 
67.8 
72.0 
45.2 
46.3 
48.9 
54.0 
60.0 
47.4 
62.2 
65.2 
38 6 
40.3 
37.3 
52.3 
46.5 
39.0 
46.5 
56.6 
53.6 
47.6 
63.8 
55.8 



60.4 



Estimated; actual readings valueless on account of heavy rains. 
Highest and lowest readings are in italics. 



69 

Table 13. — Minimum Temperatures in Open at all Elevations at Station 2, Over Sphagnum Moss on the 

Marsh, Mather, Wis.. 1907 — Continued. 





September. 


October. 


Day of month. 


Sur- 
face. 


mcnes. 


5 
inches. 


inches. 


10 
inches. 


12 
inches. 


15 

inches. 


36 
inches. 


Sur- 
face 


25 
inches. 


5 
inches. 


inches. 


10 
inches. 


12 
inches. 


15 
Inches. 


36 
inches. 


1 


62.3 
43.3 
41.5 
45.7 
37.5 
35.5 
55.2 
55.9 
33.0 
31.4 
39.0 
38.8 
41.7 
56.4 
58.4 
64.6 
46.0 
57.0 
58.6 
56.4 
31.6 
25.0 
38.2 
41.0 
23.3 
27.2 
29.2 
36.0 
27.3 
S2.S 


61.2 
42.2 
40.6 
44.8 
36.0 
34.3 
55.3 
55.8 
31.0 
30.9 
37.5 
37.3 
40.2 
57.4 
53.7 
64-6 
44.1 
56.3 
58.4 
56.5 
30.3 
23.5 
37.4 
40.8 
20.6 
25.5 
27.7 
35.2 
25.6 
SO.O 


60.9 
41.9 
40.5 
44.7 
35.5 
33.4 
54.9 
55.6 
30.3 
30.3 
37.4 
36.6 
40.3 
57.3 
53.6 
64- S 
43.6 
56.0 
58.0 
57.2 
29.5 
22.7 
37.0 
40.3 
19.5 
24.7 
27.0 
34.6 
24.6 
18.8 


61.7 
43.0 
41.6 
45.8 
36.9 
34.6 
55.5 
56.3 
31.6 
31.4 
38.5 
37.7 
40.5 
58.0 
54.6 
64.8 
44.5 
56.2 
58.9 
57.5 
30.5 
23.9 
38.5 
40.7 
21.0 
26.0 
28.1 
35.4 
28.8 
19.9 


61.7 
43.5 
41.8 
46.0 
37.1 
34.6 
55.0 
54.9 
31.7 
31.5 
38.7 
37.7 
40.6 
58.0 
54.7 
64-7 
44.6 
56.4 
59.0 
57.3 
30.7 
24.3 
38.9 
41.0 
21.3 
26.0 
28.4 
35.5 
25.9 
SO. 2 


61.8 
43.9 
42,4 
46.5 
37.6 
34.7 
55.4 
56.0 
32.2 
31.7 
39.2 
38.0 
40.9 
58.3 
55.0 
64-6 
44.7 
56.4 
59.0 
57.3 
31.0 
24.5 
39.4 
41.0 
21.5 
26.4 
28.6 
35.8 
26.0 

so.s 


61.8 
44.7 
42.7 
46.8 
38.2 
35.2 
55.3 
56.0 
32.6 
31.7 
39.3 
38.1 
41.0 
58.3 
55.0 
64.0 
44.6 
56.5 
59.0 
57.7 
30.8 
24.7 
39.7 
40.5 
22.0 
26.5 
28.7 
35.7 
26.4 
gO.7 


65.0 
48.2 
44.8 
49.0 
41.1 
37.0 
55.8 
56.6 
36.4 
34.0 
41.9 
42.5 
43.1 
59.5 
57.6 
65. S 
47.4 
55.0 
60.3 
59.0 
33.9 
27.5 
42.9 
42.3 
23.0 
28.5 
30.0 
37.5 
27.3 
22.6 


29.0 

4e.i 

38.0 
29.6 
29.0 
35.7 
39.0 
20.0 
33.1 
27.7 
28.5 
24.0 
19.6 
19.8 
40.1 
31.7 
29.9 
19.4 
21.1 
25.0 
18.0 
30.0 
24.6 
21.1 
20.7 
16.5 
29.2 
15.4 
26.9 
35.0 
30.0 


27.7 
46.6 
36.6 
27.9 
27.7 
34.3 
38.1 
17.5 
32.8 
26.1 
27.3 
23.3 
16.8 
17.1 
39.8 
30.2 
28.3 
18.3 
18.1 
22.6 
14.6 
30.5 
22.4 
18. S 
17.6 
13.5 
29.3 
U.7 
26.6 
35.3 
30.2 


26.6 
45.1 
35.7 
27.3 
27.0 
33.7 
37.4 
15.9 
32.8 
25.0 
26.0 
22.7 
15.8 
15.6 
39.4 
29.4 
27.4 
17.6 
17.9 
21.9 
13.2 
30.7 
21.9 
17.7 
17.2 
12.5 
29.4 
10.0 
25.7 
34.8 
29.4 


27.8 
46.2 
36.8 
28.5 
28.4 
34.7 
38.5 
17.2 
34.5 
26.4 
27.0 
24.0 
17.0 
16.8 
40.6 
30.6 
28.4 
19.2 
19.0 
23.3 
14.2 
32.5 
23.5 
19.4 
18.9 
13.8 
30.4 
11.5 
26.3 
35.9 
30.4 


27.8 
46.2 
37.0 
28.7 
28.7 
35.1 
38.6 
17.5 
35.0 
26.5 
27.3 
24.4 
17.4 
17.3 
40.9 
31.0 
28.7 
19.6 
19.4 
23.6 
14.6 
33.0 
23.6 
19.8 
19.5 
14.0 
30.2 
12. S 
26.7 
35.9 
31.0 


28.3 
46.4 
37.0 
29.1 
29.5 
35.5 
38.7 
17.6 
35.5 
26.7 
27.5 
24.5 
17.6 
17.4 
41.3 
31.4 
28.7 
19.3 
19.6 
23.8 
14.7 
33.4 
23.7 
20.3 
19.7 
14.5 
30.0 
12.5 
26.9 
36.0 
31.5 


28.0 
46.0 
37.0 
29.6 
29.3 
35.5 
38.6 
17.8 
35.0 
26.5 
27.2 
24.3 
17.7 
17.5 
41.0 
31.4 
28.5 
19.6 
19.8 
23.7 
14 7 
33.5 
23.6 
20.6 
19.4 
14.5 
29.5 
12.5 
26.5 
35.5 
31.5 


29.9 





ei.o 


3 


39.0 


4 ■ 


33.1 


5 


33.0 


6 


41.5 




42.6 


8 


19.2 


9 


39.0 


10 


29.3 


U 


30.0 


12 


26.5 


13 


19.0 


14 


18.9 


15 . . . . 


42.0 


16 


33.1 


17 


30.0 


18 


20.5 


19 


21.0 


20 


25.3 


21 


15.0 


00 


35.4 


23 


24.0 


24 

25 


22.5 
21.9 


26 

27 

28 


14.9 
29.8 
IS. I 


29 


26.4 


30 


35.6 


31 


32.6 


















Means 


41.9 


40.8 


40.4 


41.3 


41.4 


41.7 


41.8 


43.8 


27.5 


26.0 


25.2 


26.5 


26.8 


27.1 


27.0 


28.9 







Table 13a. — Monthly and Seasonal Means of Minimum Temperatures in Open at all Elevations, Station 2, 

Mather, Wis., 1907. 



May.' 



July. 



August. 



Septem- 
ber. 



Means. 



Surface 36. 8 

2J inches S6.0 

5 inches 36. 2 

7Unches 36.4 

10 inches 36. 7 

12 inches 36.0 

15 inches 36. 3 

36 inches 38.8 



43.3 
4£.2 
42.3 
42.5 
42.7 
42.7 
43.5 
45.4 



62.0 



49.4 
49.6 
50.1 
62.1 



49.4 
47.4 
47.1 
47.5 
47.3 
47.5 
47.8 
60.1 



41.9 
40.8 
40.4 
41.3 
41.4 
41.7 
41.8 
43.8 



a Means for twenty days. 
Highest and lowest readings are in italics. 



27.5 
26.0 
26.2 
26.5 
26.8 
27.1 
27.0 
28.9 



41.8 
40.3 
40.1 
40.6 
40.7 
40.8 
41.1 
43.1 



70 

Table 1-4. — Minimum Temperatures in Open at all Elevations at Station 9, over Sandy Loaj^on the 

Upland, Mather, Wis., 1907. 



Day of month. 



9. 
10.. 
11. 
12. 
13. 
14. 
15. 
16. 
17. 
18. 
19. 
20. 
21. 
22. 
23. 
24. 
25. 
26. 
27. 
28. 
29. 
30. 
31. 



Means. 



Mav." 



Sur- 
face. 



21 
inches. 



36.7 
57.9 
46.6 
38.3 
35.6 
41.0 
43.7 
35.9 
SI 9 
U.9 
44.6 
44.3 
41.9 
44.8 
45.8 
30.0 
31.0 
37.2 
44.5 
47.8 



39.! 



5 
inches. 



36.7 
SB. 8 
45.2 
36.3 
35.0 
39.4 
44.7 
34.9 
23.7 
SS.9 
44.2 
44.0 
41.8 
43.9 
45.1 
31.4 
30.8 
36.1 
42.0 
46.8 



36.7 
59.8 
45.0 
36.0 
34.8 
39.1 
44 9 
35.0 
23.8 
IS.O 
44.2 
44.0 
41.8 
44.0 
45.1 
31.6 
31.1 
36.3 
42.3 
46.8 



39.3 



inches. 



10 
inches. 



37.0 
60.5 
45.2 
36.1 
34.8 
39.3 
45.3 
35.7 
24.0 
S3.1 
44.6 
44.0 
41.8 
43.9 
45.2 
32.0 
31.6 
36.7 
42.2 
46.9 



39.5 



12 
inches. 



15 36 
inches, inches. 



June. 



Sur- 
face. 



2i 
inches. 



37.0 


37.0 


58.7 


58.5 


45.0 


45.1 


36.1 


36.0 


35.0 


35.0 


39.3 


39.1 


45.6 


46.0 


36.0 


36.0 


24.8 


24.9 


SS.l 


$S.l 


44.1 


44.2 


44.0 


44.0 


41.9 


42.0 


44.0 


44.0 


45.0 


45.1 


32.0 


31.9 


31.5 


31.6 


36.8 


37.0 


42.1 


42.0 


46.8 


46.8 



37.0 
60.5 
46.0 
36.0 
33.3 
39.3 
46.0 
36.0 
25.0 
SS.O 
44.3 
44.0 
41.6 
43.9 
45.0 
32.0 
31.8 
36.9 
42.0 
46.4 



39.4 



37.0 
60.9 
44.9 
35.5 
34.9 
39.4 
47.0 
36.9 
25.9 
£3.8 
44.0 
44.0 
42.0 
46.7 
45.0 
32.1 
32.0 
37.6 
42,8 
46.4 



39.9 



33.8 
36.9 
53.5 
44.0 
42.1 
Si. 7 
47.7 
34.6 
40.9 
54.0 
45.5 
53.0 
42.0 
38.9 
42.5 
54.5 
67.1 
59.0 
55. 1 
51.6 
49.8 
60.9 
59.1 
55.0 
56.9 
47.0 
44.8 
46.0 
52.1 
56.2 



48.7 



32.2 
34.3 
53.6 
40.3 
42.5 
Sl.i 
46.5 
31.8 
37.9 
53.3 
43.5 
52.3 
40.0 
36.0 
41.0 
52.0 

ee.i 

55,8 
54.8 
47.8 
46.3 
60,7 
57.4 
53.2 
50.7 
47.0 
42.7 
42.0 
47.8 
53.9 



inches. 



32.2 
34.8 
63.8 
40.4 
42.9 
Sl.S 
46.5 
31.8 
37.9 
53.4 
43.7 
52.5 
41.1 
36.1 
41.0 
52.0 
66.5 
55.7 
54.9 
47.9 
46.6 
60.6 
57.7 
53.2 
56.5 
47.2 
42.8 
42.1 
48.0 
64.1 



7J 
inches. 



10 I 12 
inches. .inches. 



32.3 
34.9 
54.0 
40.5 
43.0 
SI. 7 
46.8 
31.8 
37.9 
63.5 
43,8 
52,6 
41,2 
36,2 
41,0 
52,1 
66.4 
55,7 
55,0 
47,9 
46.9 
60,5 
67,9 
.53,1 
56,7 
47,3 
42,9 
42,0 
48,1 
54,4 



15 
inches. 



I 



32,4 
34,9 
53,8 
40,6 
43.0 
St.7 
46.7 
31.8 
37.8 
53.4 
43.9 
52.3 
41.2 
36.0 
40.8 
62.0 
66.8 
56.7 
54,9 
47,9 
46,9 
60,6 
57,9 
53,0 
56,6 
47,3 
42,9 
41,9 
48,0 
54,2 



32,2 
34.9 
54.0 
40.5 
43.0 
SI. 7 
46,7 
31,8 
37,8 
53,5 
44.0 
52.0 
41.3 
36.1 
40.9 
52.0 
67.9 
55.8 
64.8 
47.7 
46.9 
60.7 
58,0 
53,0 
56,6 
47,1 
42,9 
41,7 
48,0 
54,3 



46,9 ! 46,9 



32,3 
34,8 
54,0 
40,4 
43,0 
St.g 
46.6 
Sl.S 
37.6 
53,7 
43,9 
52,0 
41,3 
36,0 
40,5 
52,0 
66.9 
55,5 
54.9 
47.8 
46.9 
60.8 
58.1 
53.0 
56.8 
47.3 
43.2 
41.8 
49.2 
54.4 



36 
inches. 



46.9 



33.1 
35.5 
54.3 
40.1 
43.7 
31.4 
46.7 
31.8 
37.6 
52.9 
44.2 
52.0 
41.9 
36.0 
40.6 
52.0 
67.3 
65.8 
65.0 
47.9 
46.4 
60.9 
68.5 
62.9 
56.8 
47.4 
43.3 
41.7 
49.3 
65.0 



a Means for twenty days. 
Highest and iowest readings are in italics. 



71 

Table 14. — Minimum Temperatures in Open at all Elevations at Station 9, over Sandy Loam on the 

Upland, Mather, Wis., 1907 — Continued. 



Day of month. 



1. 
2. 
3. 
4. 

5. 

6. 

7. 

8. 

9. 
10. 
11. 
12. 
13. 
14. 
15. 
IG. 
17. 
18. 
19. 
20. 
21. 
22. 
23. 
24. 
25. 
26. 
27. 
28. 
29. 
30. 
31. 



Meatis 55.0 



July. 



Sur- 
face. 



2J 
inches. 



67.8 
SS.3 
49.6 
52 
54.3 
59.4 
52.7 
56.3 
61.4 
51.9 
61.6 
48.4 
62.0 
61.5 
68.0 
54.1 
54.9 
51.4 
56.6 
59.0 
65.6 
62.5 
50.4 
62.0 
52.8 
47.8 
44.6 
57.1 
65.0 
50.9 
55.1 



5 
inches. 



inches. 



57.8 
33.9 
45.0 
49.5 
60.0 
57.3 
49.0 
56.2 
59.9 
47.6 
60.1 
47.0 
49.4 
60.0 

es.o 

50.4 
53.9 
49.0 
55.1 
58.9 
64.0 
63.0 
49.9 
63.1 
51.6 
47.8 
43.4 
56.9 
55.0 
49.9 
55.7 



53.8 



10 
inches. 



67.9 
Si. I 
45.2 
49.8 
60.5 
57.6 
49.0 
56.5 
60.0 
47.6 
60.1 
47.3 
49.5 
60.1 
68.0 
50.2 
54.2 
49.0 
65.1 
59.1 
63.7 
63.0 
50.0 
63.4 
51.5 
47.8 
43.2 
57.1 
56.2 
50.0 
56.0 



12 
Inches. 



53.9 



57.7 
Si-S 
45.2 
49.6 
60.3 
57.3 
48.9 
66.4 
59.8 
47.3 
60.1 
47.4 
49.7 
60.2 
67.9 
60.1 
64,0 
48.8 
55.0 
59.0 
63.5 
63.0 
50.1 
63.4 
51.4 
47.7 
43.1 
67.1 
55.0 
49.9 
55.8 



63.8 



15 
inches. 



57.9 
34.7 
45.3 
49.6 
60.7 
57.4 
48.9 
66.6 
60.0 
47.2 
60.1 
47.5 
49.8 
60.3 
68.0 
60.0 
54.1 
48.9 
55.2 
59.0 
62.8 
63.0 
50.3 
63.7 
51.5 
47.8 
43.1 
57.0 
55.2 
60.0 
56.0 



53.9 



57.9 
3i.8 
45 5 
49 7 
60.8 
57.5 
49.0 
56.7 
60.0 
47.4 
60.2 
47.8 
49.9 
60.5 
68.0 
50.1 
54.2 
48.8 
54.0 
69.2 
63,6 
63.3 
60.5 
63.8 
51.5 
47.9 
43.1 
57.4 
56.3 
50.1 
56.0 



54.0 



36 
inches. 



5.S. 
3S.0 
45.9 
49 3 
59.4 
57.4 
48.9 
57.1 
60.0 
47.1 
60.0 
48.9 
60.1 
60.9 
68.3 
50.0 
54.6 
48.7 
64.0 
59.5 
63.0 
63.4 
50.6 
64.1 
51.3 
48.0 
43.0 
57.9 
55 9 
50.4 
56.3 



54.1 



August. 



Sur- 
face. 



51. 
43.9 
46.7 
S8.7 
59.0 
52.9 
55.0 
55.2 
52.1 
53.1 
71.1 
60.0 
48.4 
51.0 
54.2 
62.0 
49.9 
54.8 
65.1 
42.0 
45.2 
41.6 
52.0 
49.5 
44.0 
51.7 
58.0 
65.6 
51.7 
64.0 
57.4 



2.1 
inches, inches. 



52.8 
43.8 
46.5 
37. B 
58.2 
51.0 
55.0 
53.6 
62.0 
51.9 
71.0 
49.0 
47.4 
50.2 
53.8 
61.0 
48.9 
54 
64.8 
40.6 
44.5 
40.7 
61.9 
49.9 
43.8 
48.7 
57.0 
54.7 
50.6 
63.7 
56.4 



inches 



62.1 



51.8 



52.8 
43.9 
46.5 
37.7 
58.2 
51.3 
55.1 
53.8 
61.9 
62.0 
70.9 
49.0 
47.5 
50.4 
54.0 
61.3 
49.0 
54.2 
65 
40.8 
44.7 
40.8 
52.4 
50.0 
44.2 
49.0 
57.0 
54.9 
60.6 
63.8 
56.7 



51.9 



52.9 
44.0 
46.7 
37.6 
58.1 
51.5 
5.5.2 
54.0 
51.9 
51.9 
71.0 
49.1 
47.6 
50.8 
64.4 
61,2 
49.4 
54.4 
64.9 
41.8 
44. S 
41.0 
52.8 
50.0 
44.3 
49.1 
57.2 
55.1 
50.4 
63.8 
57.0 



62.0 



10 
inches. 



12 
inches. 



52.6 
44.0 
46.6 
37.6 
58.0 
51.5 
55.1 
53.7 
51.8 
51.7 
71.3 
49.1 
47.5 
50.6 
54.1 
61.2 
49.2 
54.4 
64 7 
41.0 
44.6 
40.9 
52.4 
50.7 
44.3 
49.0 
56. 7 
55.0 
50.4 
63.7 
57.0 



51.9 



52.7 
44.0 
46.6 
37.4 
68.2 
51.8 
55.4 
64.0 
61.7 
51.7 
71.S 
49.3 
47,5 
50,9 
54,5 
61,3 
49.5 
54.5 
64.8 
41.0 
44.7 
40.9 
62,6 
50.2 
44,5 
49.1 
57.0 
55 2 
60.5 
63.9 
57.2 



52.1 



15 
inches 



52.7 
44.1 
46.7 
37.5 
58.6 
62.0 
55 6 
53.8 
51.7 
51.8 
71.6 
49.2 
47.5 
50.9 
54.4 
61.4 
49.5 
54.9 
65.0 
40.9 
44.6 
40.7 
52.6 
50.8 
44.5 
49.1 
57.0 
55.2 
50.2 
63.8 
57.1 



30 
inches. 



52.8 
44.1 
46, 8 
37.2 
58.3 
51.6 
66.0 
53.6 
61.6 
61.8 
72.0 
49.6 
47.5 
60.8 
64.6 
61.2 
49.7 
54.0 
64.1 
41.2 
44.5 
40.8 
52.7 
51.9 
44.7 
49.1 
56, 5 
65.4 
50.1 
63.7 
57.2 



51.8 1 



52.; 



Highest and lowest readings are in italics. 



72 



Table 14. — Minimum Temperatures in Open at all Elevations at Station 9. over Sandy Loam on the 

Upland, Mather, Wis., 1907 — Continued. * 











September. 














October. 








Day of month. 


Sur- 
face. 


25 
inches. 


5 
inches. 


7* 
inches. 


10 

Inches. 


12 
inches. 


15 
inches. 


36 
inches. 


Sur- 
face. 


mches. 


5 
inches. 


75 
inches. 


10 
inches. 


12 
mches. 


15 

inches. 


36 
inches. 


1 


6B.7 
51.0 
48.9 
52.0 
4S.3 
40.4 
56.0 
56.9 
38.6 
38.7 
45.7 
44.6 
47.3 
56.5 
56.6 
65.0 
52.4 
58.1 
60.3 
57.3 
36.7 
28.0 
42.2 
42.2 
26.4 
31.2 
32.6 
38.0 
29.2 
iS.O 


ee.B 

51.3 

48.8 
61.8 
43.5 
39.4 
55.6 
56.6 
38.2 
36.8 
45.0 
44.7 
46.3 
56.7 
56.8 
64.7 
50.3 
57.7 
60.0 
58.4 
35.1 
27.8 
42.2 
42.3 
26.2 
29.3 
31.5 
37.9 
28.6 


66.7 
51.4 
48.9 
52.0 
43.6 
39.4 
55.6 
56.7 
38.4 
36.8 
45.4 
44.8 
46.3 
57.4 
57.5 
64.8 
50.4 
57.7 
59.9 
58.6 
35.3 
27.8 
42.4 
42.4 
26.3 
29.3 
31.6 
38.0 
28.6 
2i.7 


a 

66.7 
51.6 
49.0 
52.2 
43.6 
39.4 
55.7 
56.7 
38.5 
36.9 
45.5 
44.9 
46.4 
57.2 
57.2 
64.8 
50.5 
57.8 
60.0 
58.8 
35.5 
28.1 
42.5 
42.4 
26.4 
29.4 
31.6 
38.2 
28.7 
25.0 


66.7 
61.6 
48.9 
61.8 
43.5 
39.4 
55.5 
56.7 
38.4 
36.7 
45.5 
45.0 
46.3 
57.5 
57.6 
64.7 
50.4 
57.6 
59.7 
58.7 
34.6 
28.3 
42.5 
42.3 
26.4 
29.3 
31.4 
38.1 
28.6 
15.1 


67.0 
51.6 
49.1 
52.1 
43.5 
39.4 

55:7 

56.6 
38.3 
36.7 
45.5 
45.0 
46.5 
67.9 
57.9 
65.0 
50.5 
57.6 
60.3 
58.3 
35.5 
28.0 
42.5 
42.4 
26.4 
29.4 
31.6 
38.2 
28.6 
15.1 


67.0 
51.7 
49.0 
52.0 
43.5 
39.2 
55.6 
56.6 
38.3 
36.7 
45.5 
45.0 
46.4 
58.1 
58.0 
65.0 
50.4 
57.7 
60.2 
58.6 
35.5 
28.2 
42.6 
42.6 
26.5 
29.4 
31.5 
38.2 
28.5 
15. i 


67. B 
51.7 
49.0 
51.9 
43.5 
39.1 
53.5 
56.5 
38.4 
36.5 
45.5 
45.4 
46.4 
57.3 
56.8 
65.0 
50.1^ 
57.3' 
60.1 
58.8 
35.6 
28.6 
42.6 
41.5 
26.5 
29.5 
31.4 
38.0 
28.3 
25.4 


33.8 
49.6 
44.4 
37.7 
38.0 
42.1 
46.1 
22.5 
36.4 
31.6 
33.0 
27.4 
21.5 
21.7 
42.2 
36.4 
34.4 
23.2 
23.8 
25.4 
18.4 
34.4 
26.6 
23.4 
24.6 
16.7 
32.6 
15.2 
29.9 
36.7 
33.9 



32.2 
Ji9.6 
43.5 
38.3 
38.7 
41.6 
45.0 
20.0 
37.2 
31.2 
33.6 
28.0 
21.6 
18.8 
42.5 
35.5 
33.8 
23.0 
22.7 
25.7 
15.6 
31.9 
26.5 
23.0 
25.3 
14.8 
32.8 
tS.5 
28.8 
36.6 
34.0 


32.3 
BO.O 
43.6 
38. 4 
39.0 
41.8 
45.3 
19.8 
37.5 
31.5 
33.7 
28.0 
21.6 
18.9 
42.6 
35.6 
34.2 
23.0 
23.0 
25.8 
15.6 
35.7 
26.6 
23.2 
25.3 
14.8 
33.2 
IS.B 
29.0 
36.7 
34.3 


32.4 
50. S 
43.6 
38.6 
39.3 
42.3 
45.5 
19.8 
37.7 
31.7 
33.8 
28.4 
21.6 
19.3 
42.6 
35.5 
34.4 
23.2 
23.6 
26.1 
16.2 
36.3 
26.8 
23.3 
25.5 
14.8 
33.4 
1S.8 
29.0 
36.7 
34.3 


32.4 
50.S 
43.6 
38.6 
39.4 
42.4 
45.5 
19.7 
37.7 
31.8 
33.8 
28.3 
21.6 
19.3 
42.6 
35.5 
34.4 
23.1 
23.6 
26.0 
16.2 
36.4 
26.8 
23.3 
25.5 
14.8 
33.3 
1S.8 
29.1 
36.6 
34.4 



32.2 

50.6 
43.5 
38.6 
39.4 
42.5 
45.6 
19.7 
37.9 
31.8 
33.8 
28.2 
21.8 
19.3 
42.7 
35.4 
34.4 
23.0 
23.6 
26.1 
16.2 
36.4 
26.8 
23.4 
25.5 
14.8 
33.3 
IS. 8 
29.1 
36.4 
34.4 


32.4 
50.7 
43.7 
38.6 
39.3 
42.8 
45.6 
19.6 
38.0 
31.9 
33.9 
28.2 
21.7 
19.3 
42.8 
35.5 
34.4 
23.0 
23.6 
26.0 
16.2 
36.7 
26.9 
23.5 
25.6 
14.7 
33.4 

U.0 

29.0 
36.6 
34.5 


32.1 


2 


51.1, 


3 . 


43.4 


4 


38.9 


5 ■-.... 


39.6 


6 


43.6 


7 


45.7 


8 


19.5 


9 .. 


38.5 


10 

11 

12 


32.0 
34.0 
28.4 


13 


21.7 


14 


19.3 


15 ." 


42.8 


16 


35.0 


17 


.34.6 


18 


23.0 


19 


23.7 


20 


26.1 


21 


15.8 


22 


37.3 


23 


27.0 


24 


24.0 


25 

26 

27 

28 

29 

30 

31 


25.7 
14.6 
33.1 
H.l 
28.9 
36.1 
34.7 










• 1 






Means 


45.6 


45.2 


45.3 


45,4 


45.3 


45.4 


45.4 


45.3 


31.1 


30.5 


30.8 


31.0 


31.0 


31.0 


31.0 


31.1 



Table \Aii. — Monthly and Seasonal Means of Minimum Temperatures in Open at all Elevations, Station 9, 

Mather, Wis., 1907. 



May." 



Surface S9.9 

2i inches _ 39.2 

5 inches 39. 3 

7 J inches 39.5 

10 inches 39. 4 

12 inches I 39.5 

15 inches - I 39.4 

30 inches ' 39.9 



June. 



i8.7 
46.7 
46.8 
46.9 
46.9 
46.9 
46.9 
47.1 



£5.0 
55.7 
53.8 
53.9 
53.8 
53.9 
54.0 
54.1 



.\ugust. 



51.6 
St. 8 
51.9 
52.0 
51.9 
52.1 
51.8 
52.1 



Septem- 
ber. 



45. e 
45.2 
45.3 
45.4 
45.3 
45.4 
45.4 
45. 3 



a Means for twenty days. 
Highest and lowest readings are in italics. 



31. 1 
30.5 
30.8 
31.0 
31.0 
31.0 
31.0 
31.1 



Means. 



45.5 
44-5 

44.6 
44.8 
44.7 
44.8 
44.8 
44.9 



73 

Comparison of xcind movement over upland and marsh, and effect on temperature, Mather, 
Wis., 1907. — Not as mucli variation in temperature occurred at Station 9 as at Station 2, 
because the former was on the upland where there was more lireeze, which mixed the air at different 
elevations. On clear, cool, quiet nights the cold air settles gradually through gravity toward 
the surface of tlie earth, hut if the night is windy, tlie air at different elevations is mixed together 
so that the temperature of the air over a considerable area is nearly uniform. The greatest 
difference locally is on a clear night when a calm prevails, so that there is no interference with 
the gradual settling of the cold, heavy air to the surface. 

Of course the velocity of the wind is least near the sui'face of the earth, due to friction, 
and the velocity increases witli the elevation. Anemometers placed on the upland and 
on the bog at Mather show that the variation, even for a slight elevation, is quite 
decided. (See Tables 15 and 15a.) The anemometer on the upland was located on the 
cupola of the warehouse, 32 feet 7 inches above the ground and 45 feet 10 inches above 
the level of the instrument on the marsh. (Fig. 16.) The mean hourly velocity of the wind 
on the upland for the five months, June to October, inclusive, was 9 miles, while on the marsh 
it was just half that amount, 4.5 miles. This proportion, moreover, was maintained for the 
various months. The highest average hourly movement for both exposures was from 12 to 1 
p. m., it being 13.7 miles on the upland and 7.9 miles on the bog. The lowest average for any 
one hour was 6.3 miles on the upland between 2 a. m. and 3 a. m., while on the lowland the 
lowest was 2.3 miles, this occurring between 9 p. m. and 10 ]i. m., and also from midnight to 
4 a. m. For some reason the average on the lowland was slightly higlier between 10 p. m. and 
midnight, while on the upland there was a gradual decrease every hour from the maximum at 
1 ]i. m. to the minimum at 3 a. m. The lowest hourly average movement in the individual 
months occurred in only one hour in each case. As a rule there was a falling off of the wind 
after the hour of greatest heat, the movement declining more rapidly in proportion over the 
bog than on the upland. Frequently at night an absolute calm prevailed on the bog. 

On several mornings when there was a moderate to fresh wind velocity there was usually 
a difference of less than 2° between the extremes of the various thermometers at Station 2 on 
the bog. On August 19, when a fair breeze prevailed, this difference was only 0.6°. There 
were, on the other hand, many instances of nights of either light wind or of no wind, when a 
great variation occurred in the readings of the thermometers at different elevations, as on May 
30, June 30, July 7 and 13, and October 14, the range at Station 2 being from 4° to 5°. When 
the wind over tlie ])og was light or calm during the night, the variation m temperature was 
invariably greater than the average, and when there was a breeze at night the variation was less. 

Because of the greater movement of the air with increased elevation, the temperature 
of the air over the upland did not vary as much as on the bog. While there was an average 
extreme difference of 3.1° between all the readings at Station 2 on the bog for the season, this 
difference at Station 9 on the upland amounted to only 1°. (Tables 13(7 and 14a.) 



74 

Table 15.— Average Hourly Wind Velocity on Upland and Marsh, Mather, Wis., 1907. 



Hour olihi.v- 


June. 


July. 


August, 


September, 


October 
(30 days). 


Means. 


Up- 
land. 


Marsh. 


Up- 
land. 


Marsh. 


Up- 
land, 


Marsh. 


Up- 
land. 


Marsh. 


Up- 
land. 


Marsh, 


Up- 
land. 


Marsh. 




6.4 
6.5 

e.i 

6.2 
6.6 
6.7 
7.8 
10.1 
10.8 


1.9 
1.9 
US 
1.9 
2.1 
2.9 
4.0 
5.3 
6.1 
6.4 
6.9 
7.1 
7.2 
7.S 
7.0 
7.0 
6.5 
5.5 
3.9 
2.3 
2.1 
2.0 
2.3 
2.1 


S.2 

5.5 

S.S 

5.6 

5.6 

5.4 

6.0 

7.1 

7.3 

9.2 

10.1 

10.4 

11.1 

11.4 

11.8 

11.5 

11.2 

9.4 

6.9 

5.3 

5.5 

5.9 

5.9 

5.8 


1.8 
1.8 
1.9 
1.7 
1.9 
2.5 
3.4 
4.0 
4.7 
5.5 
6.0 
6.4 
6.7 
6.8 
7.0 
6.9 
6.3 
5.3 
3.4 
1.9 
1.6 
1.9 
2.2 
2,2 


5,9 
S.7 
6.1 

e.7 

5.7 
5.6 
7.2 
8.1 
10.0 
11.4 
12.0 
12.5 
H.0 
13.3 
12.9 
13.1 
11.6 
9.5 
8.0 
6.9 
6.6 
6.3 
6.3 
6.3 


2.0 
2.0 
2,0 
1.9 
2,3 
2,6 
3.5 
4.6 
5.8 
6.6 
6.9 
7.5 
8.2 
7.9 
7.5 
7,6 
6,7 
5,3 
3.5 
2.9 
2.3 
2.0 
2.3 
2.3 


7.3 

7.7 

7.1 

7.6 

8.1 

8.1 

8.1 

9.1 

10.8 

12.9 

14.2 

14.6 

IB. 8 

14.8 

14.3 

13.2 

11.2 

8.5 

7.3 

7.5 

7.8 

7.5 

7.6 

7.7 


2.9 
3.1 
2.7 
3,1 
3,6 
3.7 
3.9 
5.0 
6.0 
7.1 
8.3 
8.6 
8.7 
8.5 
8.1 
7.5 
6.4 
4.5 
3.0 
3.1 
3.2 
2.8 
3.2 
3.0 


7.0 

7,1 

7,1 

7.5 

7.5 

7.4 

7.4 

8.8 

11.3 

13.0 

13.1 

13.4 

li,.7 

13.6 

13.9 

13.5 

11.1 

8.3 

7.9 

7.7 

7.7 

7.7 

6.9 

7.2 


2,8 
2,8 
3,0 
2,8 
3,2 
3,1 
3,3 
4,3 
6.1 
7.4 
7.6 
8.0 
8.7 
8.1 
8.1 
7.5 
6.1 
3.7 
3.1 
3.1 
3.1 
3.0 
2.8 
2.6 


6.4 
6.5 
6.S 
6.5 
6.7 
6.7 
7.3 
8.6 
10.0 
11.3 
12.4 
12.8 
IS. 7 
13.5 
13.2 
12.8 
11.5 
9.2 
7.7 
6.8 
6.8 
6.8 
6.7 

e.7 


S.S 




2.3 




2.S 


4 a. m . - - . 


2.S 




2.6 




3.0 










9 a. m 


5 5 


10 a. ni - 

11 a. m 

12 noon 

Ip.m 

2 p. m 

3 p. m 

4p. m 


11.9 

12.5 
13.1 
12.9 
IS.i 
13.0 
12.8 
12.3 
10.3 
8.2 
6.8 
6.6 
6.7 
6.9 


6.6 
7.1 
7.3 
7.9 
7.7 
7.5 
7.3 


6p, m 

7p.m 

8p. m 

9p.m 

10 p. m 


5.9 
3.4 
2.7 
2.5 

s s 


11 p. m 


2 6 




6.7 


2 4 






Means 


9.2 


4.3 


7.7 


3,9 


8.8 


4.4 


9.9 


5.0 


9,6 


4.8 


9.0 


4 5 







Anemometer on warehouse (uplaad), 32 feet 7 inches above ground. 
Anemometer on marsh, 4 feet 7 inches above ground (Station 4). 
Anemometer on warehouse, 59 feet 5 inches above surface of marsh at Station 4. 
Difference between elevations of anemometers, 45 feet 10 inches. 

Table 15a. — Average Velocity op the Wind, by Months, on Marsh and ITpland, together with AvEitAr.E 

FOR Five Months, Mather, Wis., 1907. 



June. 



July. 



Upland . 
Marsh . . . 



9.2 

4.3 



7.7 
3.9 



August, 



Septem- 
ber. 



9.9 
S.O \ 



9.6 
4.8 



Means. 



SJ.O 
4.. 5 



Illgh'^t and lowest readings arc in italics. 

As has been said before, the air over the bog was often light and even calm on clear, lool 
nights. When the breeze freshened, the temperature invariably rose near the surface of the 
bog, although it might at the same time fall on the upland. At Station 5, under such conditions, 
on July 27, 1906, at Mather, Wis., following a fall in temperature, a rise of 9° occurred between 
2.45 a. m. and 3.45 a. m., while during a portion of that jieriod the temperature at Station 1 
fell 4°, followed by a rise of the same amount. When the breeze subsided after 4 a. m., the 
temperature fell again both on the upland and the moorland. With the freshening of the 
wind, the air over the moorland at different elevations evidenth' became mixed together and 
a rise in temperature was the result. Over the ujjland, 15 feet higher, although a fall in tem- 
perature occurred with the first freshening of the wind, the temperature began to rise later, after 
the breeze had continued for an hour, and the air at different strata for a considerable eleva- 
tion had become mixed together. (Figure 23 shows the thermograph traces and the wind 
velocity on both upland and lowland.) 



7o 



s.' 



^', 



Ui'xJM.^ 



LQWLANC 





STATION I 
STATION 5 



Fig. 23.— Mather, Wis. 
Thermograph and anemometer records on July 27, 1906, 
illustrating marked effect o£ wind on temperature on bog 
as cinnpared with that on upland. 

While at night the effect of the wiml on the temperature is often apparent, it is even more 
pronounced when .some clouds at the same time pass over the moorland. Passing clouds 
arrest the fall in temperature, and sometimes even cause the temperature to rise. A 
breeze, of course, usually attends the movement of clouds over a bog. Thermograph traces 
showmg these irregularities are quite interesting. Such a condition is illustrated by Figure 24, 
noon to noon, August 30-September 1, 1906, Berlin, Wis., showmg the trace of a tiiermograph 
located on the bog. 



AUGUST 

3oth. 
noon 



mdi 



SEPTEMBER 

31 St. ,. iSt. 

noon mat noon 




Fig. 24.— Berlin, Wis. 
Thermograph record in the marsh. From noon, September 30, to noon, October 1, 1906. 
The trace shows the effect of passing clouds upon the temperature, both day and night. 



76 



SEPTEMBER 

noon mdt. noon 



Ordinarily a breeze does not cause such a change in temperature on the uphind as^on the 
moorland. As the cold air settles over the moorland close to the surface on clear, cool nights, 
a sli'dit freshening of the wind brings warmer air from above, raising the temperature near the 
surface. This effect, however, can not always be noticed on the upland. The fall in tempera- 
ture in the shelter on the upland may be steady through the night until the coldest point has 
been reached, while at the same time the thermograph trace of the instrument placed on the 
boc may show considerable irregularity. Such a coTidition was noted during the night of 
September 4-5, 1906, Berlin, Wis., when the wind during the evening up till 11 o'clock was 

"puffy." (Fig. 25.) 

Exposed minimum thermometers over feat and sanded logs at the surface, and at elevations 
of 5 inches and 36 inches, Berlin, Wis. — Because the locations of Stations 2 and 9 at ilather 
were unlike, not only as regards the character of the soil and its covering, but also as regards 
elevation, the exposed temperatures between similar heights above the ground are not com- 
parable. If both stations had been located on the 
bog, a true comparison might be made between 
the temperatures of the two stations at several eleva- 
tions. In the case of Stations 2 and 9 the differ- 
ence in elevation is probably as important a factor 
as the difference in the character of the soil. 

In order to supplement Tables 13 and 14, Table 
16 has been prepared from daily minimum readings 
made at Berlm, Wis., during September, 1906, from 
instruments exposed at the surface, 5 inches and 
36 inches above the surface, at Stations 2 and 3, 
peat and sanded bogs, respectively, about 100 feet 
apart and on the same level. Both locations were 
comparatively clean, the portion of the bog in which 
they were located having l>een weeded in the spring 
of that year. On account of the clean surfaces 
the temperatures were naturally much higher than 
where the vegetation was dense. Another station, 
5, that was maintained at Berlin, and to which refer- 
ence has been made, was much colder than Station 
2, but a thermometer at an elevation of 36 inches 
was not included in the equipment of that station. 
The temperature at both Stations 2 and 3 aver- 
aged lowest at tlie 5-inch height, 47° and 48.6°, 
respectively. The temperature was highest at the 
surface, 50.6° and 53.6°, while at the height of 36 
inches there were intermediate values, 48.7° and 
49°, respectively. The temperature each day was 
almost invariably lowest at both locations at the 
5-inch height, as has been previously shown, and likewise almost invarialily liighest at the surface. 
While in the sanded bog the surface thermometer registered on an average 5° higher 
tlian the one at 5 inches, in the peat bog the difference was 3.6°. Moreover, the surface 
thermometer in the sanded bog registered 4.6° higlier than the one at 36 inches, while in tlie 
peat bog the difference between the thermometers similarly placed was but 1.9°. At both 
locations it was warmer at the surface than at the elevation of even 36 inches. This would 
naturally be expected over the sanded surface. As stated above, the peat soil at Station 2 
was comparatively warm, tliat portion of the bog having been thoroughly weeded at the 
beginning of the season. The peat was, of course, colder than the sanded section, am! it was 
for this reason that at Station 2 the difference between the readings at 36 inches and the surface 
was less than at Station 3 in the sanded section. 




IN VINES 
IN SHELTER 



Fig. 25.— Berlin, Wis. 
Traces of thermograph in shelter on upland and in 
vines on marsh, noon, September 4 to noon, September f^, 
1906. Uncorrected readings. The trace of instrument 
exposed in the vines is irregular, caused by variation in 
wind movement. 



77 

For similar positions at Stations 2 and 3 the average difference was greatest between the 
surface thermometers, 3°; at the 5-inch height the average difference was 1.6°, while at the 
height of 36 inches the average difference was only 0.3°. Large differences usually prevailed 
at the surface, while at 36 inches there was but a single instance of a difference of 1.5° or more, 
that being 1.6° on September 30, when the temperature was comparatively low. Sometimes 
the temperature over the peat at the greater elevation was slightly higher than over the sanded 
surface, and occasionally on days when the difference between the readings of the surface 
thermometers were marked, as on September 1, 3, 4, and 14, there was but very little difference 
at the height of 36 inches. These differences in minimum temperature should be considered 
as entirely due to differences in the character of the soil, as the vegetation ami moisture at the 
stations were practically the same. 

The surface of the peat at Station 3 was sanded, especially for the work of this investigation; 
and while the sand served to raise the night minimums at the surface and a few inches above, 
it is apparent that its influence was practically lost at an elevation of 3 feet. Ordinarily it 
should be expected that the differences between the thermometers at two stations at the same 
heights would decrease with increase of elevation, but this fact can not be demonstrated unless 
the stations are comparatively close together and all conditions favorable. At Mather, 
where the stations were far apart, the problem was more complicated. 

Table 16. — Minimum Temperatures in Open at Surface, 5 Inches above and 3 Feet Above the Surface, 
AT Stations 2 and 3, Over Peat and Sand, Respectively, together with Dip'ferences Between the 
Readings, Berlin, Wis., September, 1906. 



Day of month. 



inches. 



3 leet. 



Surface. 



Station 3. 



inches. 



3 feet. 



Differences. 



Station 2— 

surface and 

5 inches. 



station 2— 

surface and 

3 feet. 



Station 3— 

surface and 

5 inches. 



Slalion3— 

surface and 

3 feet. 



Surface. 



Differences between 
Stations 2 and 3. 



5 
inches. 



3 feet. 



10.. 

11.. 

12.. 
13.. 
U.. 
15.. 
16. 
17. 
18. 
19. 
20. 
21. 
22. 
23.. 
24. 
25. 
26. 
27. 
28. 
29. 
30.. 



Means. , 



44. 

58. 

44. 

43. 

38. 

46. 

50. 

S3. 

57. 

U2. 

65. 

62. 

54. 

35. 

45. 

56. 

59. 

61 

59. 

58, 

57. 

54. 
• 48 

35. 

47. 

53. 

S3. 

39. 

54. 

34: 



50.6 



41.6 
69.3 
39.5 
38.9 
33.1 
40.8 
47.6 
50.0 
52.4 
57.4 
SiO 
67.4 
53.0 
33.0 
44.5 
54.9 
57.3 
57.6 
58.0 
58.0 
51.4 
47.0 
43.8 
32.5 
38.7 
52.8 
31.0 
31.9 
53.6 



47.0 



45.6 
59.0 
43.2 
41.0 
34.8 
42.0 
61.2 
52.4 
54.6 
69.4 

es.g 

59.0 
53.2 
34.7 
46.6 
56.1 
58.5 
60.0 
58.6 
57.8 
55.0 
48.5 
46.5 
33.4 
40.6 
55.1 
30.4 
35.7 
63.5 
31.4 



48.7 



61.5 
58.2 
52.0 
51.0 
45.0 
52.0 
55.0 
56.8 
59.2 
64.5 
66.0 
63.9 
53.9 
43.9 
4S. 1 
56.0 
62.3 
64.0 
60.0 
60.0 
60.0 
56.1 
50.4 
41.0 
45.0 
54.8 
40.3 
43.0 
54.3 
S9.6 



45.5 
59.0 
43.5 
41.5 
35.9 
42.9 
50.0 
52.7 
54.9 
60.0 
64.6 
59.6 
52.8 
36.0 
44.7 
55.4 
59.0 
60.0 
58.1 
58.0 
54.3 
48.6 
45.0 
34.0 
40.0 
53.4 
SO. 8 
35.7 
53.5 
31.0 



45.8 
59.2 
43.5 
41.9 
36.9 
42.5 
51.0 
52.3 
54.6 
60.0 
65.6 
.59.6 
52.9 
35.1 
46.9 
56.0 
68.4 
60.5 
58. 4 
58.7 
55.3 
48.3 
45.6 
33.5 
40.8 
65.1 
SO. 3 
36.1 
53.0 
33.0 



53.6 



48.6 



49.0 



-2.6 

+0.9 

-5.4 

-4.1 

-5.3 

-5.4 

-3.2 

-3.6 ', 

-4.8 I 

-4.6 

-1.1 

-4.7 

-1.6 

-2.6 

-1.0 

-1.5 

-2.3 

-4.0 

-1.6 

-0.9 

-6.2 

-7.0 

-4.7 

-3.2 

-S.9 

-0.5 

-2.9 

-7.9 

-1.2 

-5.2 

-3.6 



+ 1.3 
+0.6 
-1.7 
-2.0 
-3.6 
-4.2 
+0.4 
-1.2 
-2.7 
-2.6 
+0.1 
-3.1 
-1.4 
-0.9 
+ 1.1 
-0.3 
-I.l 
-1.6 
-1.0 
-1.1 
-2.6 
—5.5 
-3.0 
-2.3 
-7.0 
+1.8 
-3.5 
-4.1 
-1.3 
-2.6 

-1.9 



-6.0 
+0.8 
-8.5 
-9.5 
-9.1 
-9.1 
-5.0 
-4.1 
-4.3 
-4.5 
-1.4 
-4.4 
-1.1 
-8.9 
-3.4 
-0.6 
-3.3 
-4.0 
-1.9 
-2.0 
—5.7 
-6.6 
-5.4 
-7.0 
-5.0 
-1.4 
-9. J 
-7.3 
-0.8 
-8.6 



-5.7 
+ 1.0 
-8.5 
-9.1 
-9.1 
-9.5 
-4.0 
-4.6 
-4.6 
-4.5 
-0.4 
-4.3 
-1.0 
-8.8 
-1.2 
0.0 
-3.9 
-3.6 
-1-.6 
-1.3 
-4.7 
-6.8 
-4.8 
-7.5 
-4.2 
+0.3 
-10.0 
-6.9 
-1.3 
-6.6 



-7.3 
+0.2 
-7.1 
-8.0 
-6.6 
-5.8 
-4.2 
-3.2 
-2.0 
-2.5 
-0.9 
-1.8 
+0.7 
-8.S 
-2.6 
+0.4 
-2.7 
-2.4 
-0.4 
-1.1 
-2.4 
-1.1 
-1.9 
-6.3 
+2.6 
-1.6 
-0. 4 
-3.2 
+0.5 
-5.6 



-5.0 



-3.0 



-3.9 

+0.S 

-4.0 

-2.6 
-2.8 
-2.1 
-2.4 
-2.7 
-2.5 
-2.6 
-0.6 
-2.1 
+0.2 
-2.0 
-0.2 
-0.6 
-1.7 
-2.4 
-0.1 
0.0 
-2.9 
-1.6 
-1.2 
-1.5 
-1.3 
-0.6 
+0.2 
-3.S 
+0.1 
-2.2 



-0.3 
-0.2 
-0.3 
-0.9 
-1.1 
-0.5 
+0.2 
+0.1 
-0.1 
-0.6 
-0.4 
-0.6 
+0.3 
-0.4 
-0.3 
+0.1 
+0.1 
-0.5 
+0.2 
-0.9 
-0.3 
+0.2 
-0.1 
-0.1 
-0.2 
0.0 
+0.1 
-0.4 
+0.S 
-1.6 



-1.6 



-0.3 



Highest and lowest readings arc in italics. 



78 

Maximum and minimum ietnperatures at different elevations, Station 9, Mather, Wis. — It 
having been showTi in the discussion of Table 3 that the readings of the exposed Aaximums 
and minimums located at the surface varied with increasing and decreasing vegetation, it 
seemed advisable to show the changes in maximum as well as minimum temperature at a single 
station at different elevations above the surface. Table 17 contains a summar}' of the maximum 
temperature readings at Station 9 on the upland from May to September, inclusive, 1907, at 
the surface, 5 inches and 36 inches above the surface. The exposed minimums at these eleva- 
tions are also given and are the same readings that appear in Table 14. The minimum read- 
ings, however, in this particular case are not of much importance. 

There was a steady fall in^ maximum temperature, with increasing elevation for all the 
months, it being much higher at the surface than at the elevation of 36 inches. The average 
maximum for the season at the surface was 84.1°; at 5 inches, 79.8°; and at 36 inches, 76.2°. 
The greatest differences occurred in June and July. On several days the difference exceeded 
15°, the greatest difference between the surface and 36 inches being 18.6° on July 20, when 
the surface reading was 109.3°, and that at 36 inches 90.7°. While these readings do not 
represent the ah temperature any more than the exposed minimums do, they indicate approxi- 
mately the degree of heat which affects the vegetation at different elevations. The changes, 
as a rule, are more abrupt between the surface and 5 inches than between 5 inches and 36 inches. 
The exposed maximums at the surface registered higher on an average because the surface of 
any solid upon whicli the sun shines becomes hotter than the air above, the air being heated 
slightly bj' radiation antl conduction, and largely by convection. All the time while the sun 
is shining the air resting upon the surface is warmer than the air above, the exposed maximums 
naturally registering lower with increasing elevation. On cloudy days there was but little 
difference between the readings of the various thermometers. (For state of weather see 
Table 22.) The range between the exposed maximum and minimum temperatures was almost 
always greater at the surface than at the other positions, this tlifference also decreasing with 
increase of elevation. 

Table 17. — Monthly and Seasonal Means of Maximum and Minimum Temperatures in the' Open at 

Different Elevations, Station 9, Mather, Wis,, 1907. 





May.a 


June. 


July. 


Aug. 


Sept. 


Means. 


Surface: 

Maximum. 


69.2 
40.0 


89.4 
48.7 


93.7 
55.0 


87.4 
52.6 


80.8 
45.6 


84 1 




48.4 






Kange 


29.2 


40.7 


38.7 


34.8 


35.2 


35 7 






5 inches: 

Maximum 


65.8 
39.4 


84.4 
46.7 


88.5 
53.8 


84.3 
51.9 


75.9 
45.3 


79 8 




47.4 








26.4 


37.7 


34.7 


32.4 


30.6 


32.4 






36 inches: 


63.3 
40.1 


80. T 
47.1 


84.1 
54.1 


80.3 
52.1 


72.6 
45.3 


76.2 




47.7 






Range ^ 


23.2 


33.6 


30.0 


28.2 


27.3 


28.5 







a Means Tor nineteen days. 

Average minimnm tennperatures for the season of 1907 for all locations, together uith soil 
temperatures, Mather, Wis. — Table IS, giving the average minimum temperature for all expo- 
sures on tlie marsh at Mather for the season of 1907, together with the average departure 
from the minimum temperature in the shelter at Station 1, will supplement data already given. 
There may, at times, seem to be a discrepancy between the averages in some of the tables. 
On this account the footnotes should in every case be carefully read. Records of some instru- 
ments are available for the entire season at Mather from May 1, but in most instances the 



79 

record began on Ma}' 12. There were, however, interruptions at some stations on May 27 and 
28, on account of reflowinc; the bog in anticipation of frost. Reflowing also aflVcted the readings 
at other times (hu'ing the season. 

The principal feature of interest in Table 18 will be found in the monthly and seasonal 
departures of the various readings from those in the shelter at Station 1. We can see here at 
a glance the points of lowest and highest temperature, assuming, of course, that the temperature 
in the shelter of Station 1 is the standard. Of the minimums in shelters, those at Stations 2 
and 5 were the lowest, averaging lower than Station 1 by 3.4° and .3.1°, respectively. The 
next lowest, as should be expected, was at Station 7, the average diflerence being 2.4°. This 
station was in the scalped piece, in the midst of an extensive field of sphagnum moss. The 
average differences for the remaining stations were as follows: Station 6, old .sanded and 
heavih' vined, 1.9°: Station 4, newly sanded and heavily vined, 1°; Station 9, sandj- loam on 
tiic upland, 0.fi°: and Station 3, newly sanded and thinly vined, 0.5°. The influence of 
sanding, draining, and cultivating is well illustrated by these figures. There is usually an 
interesting relation between these average shelter readings, on one hand, and the maximum 
soil temperature and the range in soil temperature at the 3-inch depth on the other. Station 
7 is the only important exception, and this is because, altliough the soil temperature was 
relatively high in this small bare section, tiie air temperature was affected by the surrounding 
field of sphagnum moss. 

The average shelter reading at Station 9 on the uplantl was 0.1° lower tJian tliat at Station 
3, the warmest place on the bog, and the thermometers exposed in the open at the surface at 
both these stations averaged also within 0.1° of each other, the one at Station 9 being 0.1° 
higher than the one at Station 3. As has been stated before, the coldest point on the bog was 
at an elevation of 5 inches at Station 5, where the average was 6.7° below that in the shelter 
at Station 1, while the thermometer at 5 inches at Station 2 averaged 6.0° below. The greatest 
average monthly departure was also at the 5-inch heiglit at Station 5, where the radiation was 
freer than at the surface, the October minimum averaging 8.3° lower than the one in the shelter 
at Station 1, and an extreme diflerence of 14.6° was recorded on October 24. The greatest 
differences between the exposed minimums and the minimum in the shelter at Station 1 as a 
rule occured in October, when radiation was greatest, because of the long, cool nights. 

The seasonal averages of 40.2° and 40.1° at Stations 2 and 5, respectively, are so close 
that either might be selected as the coldest point. Sometimes in this bulletin the one at Station 
2 has been used, and at other times tlie one at Station 5, according as the one or the other better 
answered the purpose. Station 2, over sphagnum moss, was located outside the cranberry 
marsh proper, and was ordinarily not affected by reflowing of the marsh ; wliile Station 5 was in 
the cranberry bog, but in an uncultivated section, representing the average conditions prevailing 
in an old bog, without improvement in the way of draining, sanding, and cultivating, just as 
Station 3 shows approximately the best results prevalent in the AVisconsin bogs. Here, then, 
are wide difl'erences between the readings of 34 different thermometers in variotis portions of 
the bog and a neighboring "island." There are, of course, reasons for these variations, the 
reatlings being afl'ected by the character of the soil and vegetation surrounding each instrument, 
anil often by the height of the instrument above the soil. 

As previously stated, while sanding, up to a certain point, is of highest importance in 
preventing low night temperatures, the character of the soil is of little consequence after frost 
has entered it. This is evident because the differences between the minimum temperatures 
are not nearly so great in the month of October as in the warmer months. The temperatures 
over the sanded surfaces, as compared with the shelter readings at Station 1, are by far the 
lowest in October. At Station 3, for instance, tlie average departure at the surface for October 
was 4.5°, while the average for the entire season was but 1.3°, and in the month of July the 
average was but 0.1°. At Station 4 the minimum thei-mometer similarly located averaged 
5.7° lower than the shelter at Station 1 for October, while the average departure for the season 
was but 3.7°. These facts are in strong contrast with the conditions prevailing at Station 5, 

.^lil.lir— Bull. T— 1(1 6 



80 

over peat and moss, where the minimum thermometer at the surface in October averaged 5.3° 
lower than in the shelter at Station 1, which was only 0.2° greater than the average departure 
for the entire season, 5.1°. The greatest monthly departure at Station 5 was 5.8° in July, at 
the time it was least at Station 3. ^Vlthough the temperature at the surface at Station 3 in 
October was relative!}' low, it was, nevertheless, not as low as at the other stations in the bog. 
This may or may not show that tlie sanded surface, after frost has entered it, has greater power 
for warding off lower temperature than the peat and moss soil. It may be that after frost 
enters the soil tlie capacity for lieat does not vary with the character of the soil, and that 
rather the difference in minimum temperature over two such surfaces depends then ujxm the 
character of the vegetation, and that in this instance in October the surface thermometer at 
Station 3 averaged higher than the surface at Station 5 only because Station 3 was thinly 
vined as compared with the relatively dense vegetation at Station 5. 

As explained in previous paragraphs of this bulletin, the temperature at and near the 
sui'face of the bog is governed large!}' by the character of the soil and its covermg. That tliis 
is true may be shown by a comparison of the minimum temperature readings with the soil 
temperature readings, especially at the depth of 3 inches. Table 19 gives the average monthly 
and the seasonal readings of soil thermometers placed at depths of 3 and 6 inches at the various 
stations. This table is the summar}' of extensive data which, for lack of space, it was found 
impracticable to print. Bj' comparing Tables IS and 19 it will be found that the exposed 
minimum temperatures at the surface at the various .stations, as a rule, averaged highest where 
the 6 J), m. or maximum soil temperatures at the 3-inch depth were the greatest, and also where 
the range in soil temperature at the 3-inch depth was the greatest. Station 7 in the scalped 
piece is an exception to this rule, for reasons already given. In other words, the highest mini- 
mums occurred at places where the soil was heated considerably in the daytime, while at places 
where the soil temperature varied little on account of dense vegetation and lack of sanding 
anti tlraining, the exposed minimum thermometers registered the lowest. The range in soil 
temperature at the 3-inch depth was naturallj- much greater than at the depth of 6 inches, and 
where the covering was exceptionally dense there was practically no range in soil temperature 
at the latter depth, as at Stations 2 and 5. It is evident, by referring to Figures 20 and 22, 
and to the soil temperature figures at the 3-inch and 6-inch depths in Table 19, that the clean 
soil during the daj^time is not onl_y heated considerablj^ near the surface in the thinly A'uied 
and bare sections, but also that the heat descends to a greater depth, and it is because of this 
heat stored in the groimd that the air above does not become as cold at night. The greater 
conduction of heat b}^ the sanded soil at Station 3 and the sandy loam at Station 9 than by 
the plam peat at Station 7 is partially shown bj' the soil temperature readings at these stations, 
although a considerable portion of the heat received at Station 7 was expended in the evapo- 
ration of the superfluous moisture. The average dailj' ranges at Station 7 at the depths of 3 
and 6 inches were, respectively, 5.1° and 1.4°, while at Stations 3 and 9 the ranges were, respec- 
tively, 8.2° and 4°, and 10.1°'and 7.7°. 



81 

Table 18. — Monthly and Seasonal Means op all Minimum Thermometers, with Departures from Mean 

OF Station 1, Mather, Wis., 1907. 



station 1: 

Shelter 

Station 2 (moss over peat): 

Shelter 

Surface 

2^ inches 

5 inches 

7i inches 

10 inches '... 

12 inches 

15 inches 

36 inches 

Station 3 (newly sanded, 
thinly vined): 

Sheller 

Surface 

5 inches 

36 inches 

Station 4 (newly sanded, 
heavily vined); 

Shelter 

Surface 

5 inches 

Station 5 (peat and moss, 
heavily vined): 

Shelter 

Surface 

5 inches 

Station 6 (old sanded, 
heavily vined): 

Shelter 

Surface 

5 inches 

Station 7 (scalped peat): 

Shelter 

Surface 

5 inches 

Station 9 (sandy loam): 

Shelter 

Surface 

2J inches 

5 inches 

THnches 

10 inches 

12 inches 

1.5 inches 

36 inches 



May.a 



Month- 
ly 
mean. 



Month- 
ly de- 
parture. 



June. 



Month- 

I.v 
mean. 



Month- 
ly de- 
parture. 



38.9 
37.6 
S7.0 
SI. 2 
37.4 
37.7 
S7.0 
37.3 
39.2 



40.4 
39.3 
39.2 



41.2 
38.4 
38.8 



39.7 
37.1 
37.2 



40.4 
38.7 
38.0 

39.9 
37.6 
37.6 

41.2 
40.9 
40.1 
40.1 
40.4 
40.3 
40.3 
40.3 
40. S 



-2.8 
-4.1 
-■«•? 
-4.5 
-4.3 
-4.0 
-i-7 
-4.4 



-0.5 
-1.3 

-2.4 
-2.5 



-0.5 
-3.3 
-2.9 



-2.0 
-4.6 

-4.5 



-1.3 
-3.0 
-3.7 

-1.8 
-4-1 
-4.1 

-0.5 
-0.8 
-1.6 
-1.6 
-1.3 
-1.4 
-1.4 
-1.4 
-0.9 



45.4 
43.3 
42.2 
42.3 
42.5 
42.7 
42.7 
43.5 
45.4 



48.9 
48.8 
46.3 
45.9 



48.4 
45.2 
45.7 



45.7 
43.5 
il.S 



47.0 
44.0 
43.2 

46.3 
44.0 
43.0 

48.4 I 

48.7 I 

46.7 

46. S 

46.9 

46.9 

46.9 

46.9 

47.1 



July- 



August. 



Month-i Month- 
ly I ly de- 
mean, parture. 



55-6 



3.6 


51.8 


5.7 


52.0 


6.8 


49.2 


6.7 


49.2 


6.5 


49.2 


6.3 


49.4 


6.3 


49-6 


5.5 


50.1 


3.6 


52.1 



-0.1 
-0.2 
-2.7 
-3.1 



-0-6 
-4.0 
-3.3 



-3.3 
-5.5 



-2.0 
-5.0 

-5.8 

-2.7 
-5.0 
-6.0 

-0.6 
-0.3 
-2.3 
-2.2 

-2.1 
-2.1 
-2.1 
-2.1 
-1.9 



5S.S 
55.5 
53-0 

51.7 



54.9 
52.3 

52.4 



S3.1 
49. S 
iB.S 



53.8 
50.3 
49.6 

53.0 
51.2 
50.2 

55.4 
55.0 
53.7 
53.8 
53.9 
53.8 
53.9 
54.0 
54.1 



-3.8 
-3.6 
-6.4 
-6.4 
-6.4 
-0.2 
-6.0 
-5.5 
-3.5 



0.0 
-0.1 
-2.6 
-3.9 



-0.7 
-3.3 
-3-2 



-2.5 
-5.8 
-S.8 



-1.8 
-5.3 
-6.0 

-2.6 
-4.4 
-5.4 

-0.2 
-0.6 
-1.9 
-1.8 
-1.7 
-1.8 
-1.7 
-1.6 
-1.5 



Month-' Month- 
ly I ly de- 



September. 



mean, parture. mean, parture. mean 



50.1 


-3.8 


49.4 


-4.5 


47.4 


-6.5 


ir.i 


-e.s 


47.5 


-6.4 


47.3 


-6.6 


47.5 


-6.4 


47.8 


-6.1 


50.4 


-3.5 



53. « 
53.7 
51.2 
48.3 



53.1 
50.6 
50-6 



50.3 

48.8 
ff.l 



52.1 
49.3 
48.3 

51.6 I 
49.2 



53.4 
52.6 
51-8 
51.9 
52.0 
51.9 
52.1 
51.8 
52.1 



-O.f 
-0.2 
-2.7 
-5.G 



-0.8 
-3.3 
-3.3 



-3.6 
-5.1 
-6.8 



-1.8 
-4.6 
-5.6 

-2.3 
-4.7 
-4.9 

-0.5 
-1.3 
-2.1 
-2.0 
-19 
-2.0 
-1.8 
-2.1 
-1.8 



Month- Month- 
ly Iv de- 



44.3 
41.9 
40.8 

1,0. J, 
41.3 
41.4 
41.7 
41.8 
43.8 



-4«.7 
45.9 
44.6 
42.7 



46.3 
41.2 
44.1 



44.1 
43.0 
40.7 



45.3 
43.1 
41.7 



46.5 
45.6 
45.2 
45.3 
45.4 
45.3 
45.4 
45.4 
45.3 



-2.8 
-5.2 
-6.3 
-6.7 
-5.8 
-5.7 
-5.4 
-5-3 
-3-3 



-0-4 

-1.2 
-2.5 
-4.4 



-0.8 
-2.9 
-3.0 



-3.0 
-4.1 
-6.4 



-1.8 
-4.0 
-5.4 



Month- 
ly 



45.0 


-2.1 


42.3 


-4.8 


42.6 


-4.5 



-0.8 
-1.5 
-1.9 

-1.8 
-1.7 
-1.8 
-1.7 

-1.7 
-1.8 



Month- 
ly de- 
parture 



30.0 
27.6 
26.0 
25.2 

26.5 
26.8 
27.1 
27.0 
28.9 



31.6 
28.8 
28.5 
29.2 



31.2 
27.6 

27.4 



29.2 
28.0 

u.o 



30.8 
28.3 
26.1 

30.8 
27.9 
27.7 

Si.S 
31.1 
30.5 
30.8 
31.0 
31.0 
31.0 
31.0 
31.1 



Sea- 
sonal 
mean. 



-3.3 

-5-8 
-7.3 
-8.1 
-6.8 
-6.5 
-6.2 
-6.3 
-4-4 



-1-7 
-4.5 
-4.8 
-4-1 



-2.1 
-5.7 
-5.9 



-4-1 
-5.3 
-8.S 



-2.5 
-5-0 
-7-2 

-2-5 
-5.4 
-5.6 



4.3.4 
41.9 
40.4 
40.2 
40.7 
40.9 
40.9 
41.2 
43.3 



lfi.3 
45.5 
43.8 
42.8 



45.8 
43.1 
43.2 



43.7 
41.7 
Ifi.l 



44.9 
42.3 
41.2 

44.4 
42.0 
41.7 



Sea- 
sonal 
depar- 
ture. 



1.0 


46.2 


2.2 


45.6 


2.8 


44.7 


2.5 


44.8 


2.3 


44.9 


2.3 


44.9 


2.3 


44.9 


2.3 


44.9 


2.2 


45.1 



-3-4 
-4.9 
-6.4 
-6.6 
-6.1 
-5.9 
-5.9 
-5.6 
-3.5 



-0.6 
-1.3 
-3.0 
-4.0 



-1-0 
-3-7 
-3.6 



-3.1 
-5.1 

-e.7 



-1-9 
-4.5 
-5.6 

-2.4 
-4.8 
-M 

-0.6 
-1.2 
-2.1 
-2.0 
-1.9 
-1.9 
-1.9 
-1.9 
-1.7 



Stations 1 and 9 on upland; others ou bog 



'! Mean for eighteen days. 
One thermometer in shelter at each station; others exposed in open. 
Highest and low est readings are in italics. 



82 

Table 19. — Monthly and Seasonal Means of Soil Thermometer Readings at 3 Inch and 6 Inch Depth. 

M.\THER, Wis.. 1907. 



[The li p. m. rouciings opciirrod the previous day, and *' Ditlereuce" shows the change during the night.] 





May." 


June. 


1 

July. 


August. 


Septem- 
ber. 


October. 


Means. 


Station 2: 
















3-ineh depth— 


" 


° 


° 


» 


" 


° 


" 


6 p. m 


39.0 


56.0 


65.0 


62.3 


57 3 


40 


SI. 7 




37.5 


53.0 


02.6 


61.2 


56.5 


45.4 




Difference... 


- 2.1 


- 3.0 


- 2.4 


- 1.1 


- 0.8 


- 0.6 


- 1.7 




6-inch depth— i 
















6p. m 


34.8 


52. S 


63.2 


62.2 


58.3 


48.2 


53.3 


7 a. ra. 


34.7 


53.2 


63.4 


62.3 


58.2 


48.1 


S3. 3 




Difference.. 


- 0.1 


■f 0.4 


+ 0.2 


-1- 0.1 


- 0.1 


- 0.1 


0.0 




Station 3: ^ 
















3-inch depth— 


















55.8 


65.8 


71.8 


68.0 


63.2 


" 




7 a. m. 


48.0 


56.9 


63.1 


61.4 


55.3 


41.9 


54.4 




Difference 


- 7.8 


- 8.9 


- 8.7 


- 7.2 


- 7.9 


- 7.7 


- 8.2 




()-inch depth— 
















6p.ni... .... 


53 6 


62 1 


68 3 


65 7 


61 


47 9 


59 8 




50.0 


57.5 


63.7 


62.1 


57.1 


44.4 


55.8 






- 3.6 


- 4.B 


- 4.6 


- 3.6 


- 3.9 


- 3.5 


- 4.0 




Station 4: 
















3-inch depth— 


















50.3 


60.3 




64.6 








7 a. m 


47.5 


56.5 


63.2 


61.5 


56.5 


44.0 


54.9 




Difference 


- 2.8 


- 3.8 


- 3.7 


- 3.1 


- 2.8 


- 2.6 


- 3.1 




6-inch depth- 






























50.2 
55.0 




47.6 


56.5 


63.5 


62.3 


57.8 


46.0 






- 0.1 


- 0.0 


- 0.7 


- 0.6 


-0.7 


- 0.5 








Station 5: I> 
















3-inch depth— 
















6 p. m 


48 5 


57 9 


66 "* 


64 


57 *' 


45 9 


50 


7 a. m 


47.5 


55.6 


63.6 


62.1 


56.5 


45.5 


S5 1 






Difference 


-1.0 

- 


- 2.3 


- 2.6 


- 1.9 


- 0.7 


- 0.4 


- 1.5 


6-inch depth — 
















6p. m 


47.1 


54.8 


63.7 


02.3 


56.7 


46.7 


55.2 


7 a. m 


■17.2 


55.0 


63.5 


02.2 


66.9 


46.6 


55.2 




-f 0.1 


,+ 0.2 


- 0.2 


- 0.1 


+ 0.2 


- 0.1 








Station 6; 
















3-inch depth— 
















6 p. m 


49 4 


59 1 


65 9 


63 6 


58 5 




57 2 


7 a. ni 


47.3 


56.3 


63.4 


01.4 


56.3 


44.0 








Difference 


- 2.1 


- 2.8 


- 2.5 


- 2.2 


- 2.2 


- 2.0 








6-inch depth— 
















6 p. m 


4fi. 8 




03.2 


62.3 


58.1 






7 a. m 


46.9 


56.1 


02.9 


61.9 


57.7 


46.8 


55 4 






Difference 


-1- 0.1 


- 0.3 


-0.3 


- 0.4 


- 0.4 


- 0.3 


2 







a Means for seventeen days. 

!> On .Vugust 10 and 12 a light covering ot mo.ss was placed around and between soil thermometers at Station 3. On .\ugust 25, at Station 3 
position of bo.x on which soil tlierniograpli rested was clianged so as to allow more sunshine around soil thermometers during morning hours. On 
August 24, at Station 5 positions of soil thermographs were changed and placed under proper conditions of live moss and vines. 



Station 2. Sphagnum moss. 

Station 3. Newly sanded, thinly vlned. 

Station 4. Newly sanded, heavily vined. 

Highest and lowest readings are in italics 



Station 5. Peat with moss, heavily vlned. 
.station 0. Old sanded, heavily vined. 



83 



T-A.BLE 19. — Monthly and Season.\i, Means op Soil Thermometer Readings at .i Inch and 6 Inch Depth, 

Mather, Wi^i.. 1!)07 — Continued. 





May. 


' June. 


July. 


August. 


Septem- 
ber. 



61.4 
55.6 


October. 


Means. 


Station 7: 

3-inch depth— 

6 p. m 


49.5 
45.9 


o 

61.9 
56.2 


68.8 
63.4 




66.9 
62.0- 


48.6 
43.6 


59.5 
54.4 




DilTerence 


- 3.6 


- 5.7 


- 5.4 


- 4.9 


- 5.8 


- 5.0 


- 5.1 


Ij-inch depth- 


45.1 
44.9 


,58.7 
56.9 


66.1 
64.4 


65. 1 
63.5 


59.3 
57.7 


/ - 47.1 
45.8 


56.9 
55.5 






Difference... 


- 0.2 


- 1.8 


- 1.7 


- 1.6 


- 1.6 


- 1.3 


- 1.4 




Station 9: 

3-inch depth— 


56.8 
47.2 


69.1 
58.0 


75.2 
64.0 


70.9 
61.4 


63.5 
54.8 


53.0 
42.7 


«4.8 










- 9.6 

55.3 

4S.6 


-11.1 

67.9 
58.9 


-11.2 

74.4 
65.3 


- 9.5 

70.8 
62.8 


- 8.7 

63.0 
56.6 


-10.3 

52.0 
44.7 


-10.1 

6S.9 
56. i 


ti-inch depth- 






Difference .. 


— I'l. 7 


- 9.0 


- 9.1 


- 8.0 


- 6.4 


- 7.3 


- 7.7 





Station 7. Scalped piece, bare peat, in a field of sphagnum moss. 

Highest and lowest readings are in italics. 



Station 9. Sandy loam on upland . 



That the rau'^e in soil temperature was mucli greater at Station 3 tlian at Station 5, and 
at the 3-inch ilepth tiian at the depth of 6 inches at both stations, is shown graphically by 
Figure 20, previously referred to, which gives the hourly traces from soil thermographs for the 
season of 1907 at each station. Figures 21 and 22, which have already been discussed, bear 
ilirectly upon this question of air and soil temperatures. While the maximum at 3 inches 
occurred at both stations from 4 to 6 p. m., and the minimum from 6 to 7 a. m., the maximum 
and the minimum at 6 inches at Station 3 occurred a few hours later, and at the 6-inch depth 
at Station 5 the maximum occurred from S to 9 a. m. and the minimum about 5 p. m. The 
curve at Station 3 at the 3-inch depth is, of course, abrupt as compared with the curves at the 
other exposures. 

Figure 19, also previously referred to, shows the curve of the soil thermograph recortls at 
Stations 3, 4, and 5 for the week of September 23-30, inclusive, 1906. The great range in 
temperature in the thinly vined and newly sanded section as compared with that in the peat 
bog with moss is apparent, while the one exposed in the heavil}^ vined and newly sanded sec- 
tion has an intermediate A'alue. The changes in soil temperature at Station 3 are again shown 
to be abrupt as compared with those at the other stations, the minimum being below as much 
as the maximum was above. Of course, the location at Station 3 was responsive to changes in 
air temperature, while the changes where the vegetation was dense lagged behind and were 
relatively slight. 

A soil thermograph was located in the reservoir so as to secure a continuous record of water 
temperature 12 inches below the surface, while an air thermograph was placed in a shelter 
over the bog 5 inches above the surface. In Figure 26 are shown the curves of these two 
instruments, and also the curve of the soil thermograph over a peat and moss bog, for the week 
of September 23-30, inclusive, 1906. Here we have tin interesting illustration of the daily 
variation in temperature in three elements — air, earth, and water — within a comparatively 
small area. 



84 

In Figure 27 the curves of air temperature, water temperature, and soil tempe|jp.ture for 
the week of September 16-23, inclusive, 1906, are ilKistrated. It is interesting to note tlie 
lagging of the changes in temperature of the soil and water behmd those of the air. 

Relation hetween dew-point and minimum temperature. — A diy atmosphere permits freer 
radiation of heat from the grounfl than moist air. Moist air absorbs part of the lieat radiated 
from the ground, and consec[uently does not permit as low temperatures as when the air is diy. 
The marsh region of Wisconsin, however, is almost always humid at night, but remarkably low 
temperatures, nevertheless, occur in spite of these humid conditions. It may be that under 
such conditions the air some little distance above the bog is relativelj' dry and jiermits rapid 
radiation through it. 

It has long been supposed that a relation exists between the dew-point and the ensuing 
minimum air temperature, and that, if the dew-point at the time of observation in the evening 
was higher than 32°, fro.st should not be expected that night. It was believed that, the dew- 
point having been reached, latent heat would be given off in the operation of condensation 
and prevent any further fall in temperature. This is a plausible theory, and many cranberry 



TT^iT 



■ ■}/.■ . «•.- „\i/,. J , ,. V.-, i ,...\j, , . ....Mr, . ;. ..17,, y. „y, , ; , .y/vy;.^^/, . ;...a, . /. ,.,R.,, i'n-^>_i_liftH44. 




::H.— Temperature curves of air, soil and water tor Mather, Wis., September 23 to 30, 1906. Air temperature in shelter over bog 
temperature of water in reservoir 12" below surface, — x— x— x— x— x— x— x— x; soil temperature 3" deep in peat bog with 



- ////fS 



:;f-,:2 



:,'Iuf.T=i.7-i 



■ / 



--m^ 



^"=^£^13^ ^'—^ 



m^M^ 



-1—-^ 



■+I 



Fig. 27.— Temperature curves of air, soil and water for Stations 3 and 5, Mather, Wis., September 16 to 23, 1906. Air temperature, station 

5, in shelter, : soil temperature, station .s, 3 in. deep, — x— x— x— x — x— x— x; soil temperature, station 3, 3 in. deep . 

temperature of water in reservoir, 12 in. below surface . 

growers have confidence in it, but the observations made on the bogs show that the dew-point 
itself is no indication whatever of the ensuing minimum temperature. 

The dew-point observations were made at Mather with the Assman aspiration psychrom- 
eter exposed on the upland about 4 feet above the ground at Station 1 and on the bog about 1 
foot above the' ground at Station 4. During the season of 1907 the dew-point on the upland 
was generally lower at 9 p. m. than at 6 p. m., the average difference for the season being 1.9°. 
(Tables 20 and 20a.) However, the ensuing minimum temperature in the shelter at Station 1 
was almost invariably lower than the 9 p. m. dew-point reading, the average depression for 
the season being 3.3°. 

The latest dew-point observation made daily at Station 4 was at 6 p. m. On account of 
the larger amount of moisture prevalent on "the bog, the dew-point was naturally higher there 
than on the upland, there being an average difference between the 6 p. m. readings of 1.5°. 
The average of the dew-point readings for the season of 1907 at Station 4 was 7.6° higher than 
the mean of the ensuing minimum air temperatures in the shelter at the same station on the 
bog, as compared with an average difference of 8.2°, noted in the season of 1906. Moreover, 
at Station 4 the minimum in the open averaged 2.6° lower than in the shelter. (Table 1.) The 



85 

average temperature at one of the coldest points on the bog in the open — the .5-inch height at 
Station 2— rwas 13.7° below the average of the dew-point readings at Station 4 during the 
season of 1907. On some nights the temperature in the shelter at Station 4 was 18° to 20° 
lower than the dew-point. On one night, September 29-.30, it was 28° lower, and this in spite 
of the fact that the relative humidity on the bog earh' the previous evening was as high as 94 
per cent. The temperature in the open at Station 2 was often as much as 25° lower, and on 
September 30 it was 30° lower. In a few cases the ensuing minimum temperatures were liigher, 
as for instance on June 3 and 10, July 1 1 , August 3 1 , and October 9 and 1 .5, when the weather was 
cloudy. During cloudy weather the dew-point and the muaimum temperature at Station 4 
were often the same. According to these observations the formation of dew and fog has no 
appreciable effect in preventing the fall of the minimum temperature to a low point, such a fog 
often lying in a thin stratum over the marsh; in fact, the greatest departures often occurred on 
nights of dew and fog when the sky above was clear. Of course, latent heat is given off in the 
process of condensation, but the amount is ob^^ously small as compared witli the vast area of 
cold air overlying the moorland. Table 22 should be used in connection with Table 20 for pur- 
poses of comparison regarding fog and dew. 

It is apparent then from the above that in the moorlands the dew-point in the evening 
is no indication of the ensuing minimum temperature. Naturally if the air were drier, the tem- 
perature would fall to a lower pomt, but the air is usually humid in the bogs, as stated above. 
The vapor in the air is so great that ordinarih" on clear cool nights dew forms even at sunset. 
In spite of the fact that the air may be saturated with moisture, the temperature frequently 
continues to fall steadily through the night, demonstrating that the latent heat given off in 
condensation has but little effect in retarding the fall in temperature. The thermograph traces 
of the instruments exposed in the open often show a stead^^ decline m temperature on nights 
of dew and fog when the sky is clear. 



86 



Table 20. — Comparison- of Dew-point Readings on the Upland at 6 and 9 p. m., with Ensuing Minimum 
Temperatures in the Shelter; also of Dew-point Readings on the Marsh at 6 p. m., wit^Ensuing 
Minimum Temperatures, and Differences at Station 4; also Ensuing Minimum Temperatures in Open, 
AND Differences at Station 2, Mather, Wis., 1907. 

[Dew-point readings occurred the previous day.] 









Junt'. 






July. 


-Vugust. 




Upland, Sta- 
tion 1— shelter. 


Marsh. 


Upland, Sta- 
tion 1 — shelter. 


Marsh. 


Upland, Sta- 
tion 1— shelter. 


Marsh. 


Day 
of 

month. 




Dew- 
point. 


Station 4— 
shelter. 


Station 2— 
5 inches, 
exposed. 


Dew- 
point . 


1 
S 


Station 4— 
shelter. 


Station 2— 
5 inches, 
exposed. 


Dew- 
point. 


6 

i 

a 
S 


Station 4 — 
.shelter. 


Station 2— 
5 inches, 
eicposed. 




«3 


g 
d 

OS 


1 

a 

S 


•d 
g 
p. 


s 

a 


i 

5 


C 

S 


g 

a 


d 


£ 
d 


d 

■6 

d 


g 

5 

.§ 
c 

ia 


O 

C 
o 

1 
H 

o 


E 

.1 

c 

i 


1 


B 

d 


e 

d 

a, 


d 


i 
s 


1 


5 


1 




1 


„ 


u 


1 


o 


. 





o 


. 


. 


. 


. 


. 


c 


o 


. 


<, 







o 


o 


o 


1 


Si 


SS 


36 


S4 


SS 


+ 1 


28 


- 6 


64 


62 


59 


62 


58 


- 4 


52 


-10 


57 


68 


55 


62 


53 


-9 


47 


-15 


2 


40 


41 


39 


43 


36 


- 7 


29 


-14 


53 


50 


SS 


53 


S7 


-16 


29 


-24 


52 


47 


46 


49 


45 


-4 


39 


-10 


3 


46 


49 


55 


48 


55 


-1- 7 


53 


+ 5 


50 


60 


48 


SI 


47 


- 4 


38 


-13 


52 


53 


48 


54 


47 


- 7 


40 


-14 


4 


62 


50 


41 


51 


42 


-9 


35 


-16 


67 61 


51 


65 


51 


-14 


45 


-20 


49 


48 


39 


54 


43 


-11 


34 


-20 


5 


44 


45 


44 


42 


44 


+ 2 


38 


- 4 


66 65 


60 


66 


61 


-5 


59 


- 7 


54 


61 


59 


56 


59 


-1- 3 


58 


-F S 


6 


36 


40 


Si 


39 


36 


- 3 


SS 


-11 


70 ' 68 


S8 


70 


58 


-12 


53 


-17 


57 


56 


54 


59 


62 


- 7 


46 


-13 


7 


45 


45 


48 


48 


48 





45 


- 3 


56 1 54 


51 


60 


61 


- 9 


43 


-17 


70 


63 


57 


71 


56 


-15 


48 


-23 


8 


38 


39 


36 


42 


SS 


- 7 


iS 


-14 


69 67 


59 


67 


55 


-12 


47 


-20 


58 


, 57 


55 


62 


56-6 


51 


-11 


9 


39 


39 


41 


42 


40 


- 2 


32 


-10 


62 


63 


61 


63 


60 


- 3 


51 


-12 


69 


59 


54 


60 


54-6 


49 


-11 


10 


47 


43 


54 


46 


55 


-1- 9 


53 


-1- 7 


57 


56 


50 


59 


50 


- 9 


42 


-17 


70 


69 


59 


69 


60-9 


56 


-14 


11 


60 


57 


47 


61 


46 


-15 


39 


-22 


59 


60 


60 


59 


61 


+ S 


60 


+ 1 


71 


70 


74 


72 


70-2 


70 


- 2 


12 


54 


50 


53 


54 


53 


- 1 


50 


- 4 


60 


60 


51 


60 


48 


-12 


42 


-18 


56 


i2 


53 


57 


49-8 


40 


-17 


13 


51 


50 


44 


54 


42 


-12 


34 


-20 


60 


69 


54 


61 


52 


- 9 


44 


-17 


56 


57 


60 


58 


49-9 


i2 


-16 


14 


46 


48 


39 


50 


40 


-10 


31 


-19 


62 


69 


62 


62 


62 





56 


- 6 


58 


59 


53 


59 


53 - 6 


46 


-13 


15 


51 


53 


43 


60 


41 


-19 


35 


-SS 


69 


67 


6S 


68 


68 





68 





64 


60 


56 


64 


56-8 


50 


-14 


16 


56 


54 


54 


56 


53 


- 3 


46 


-10 


64 


60 


51 


66 


52 


-14 


46 


-20 


66 


64 


61 


66 


62 


- 4 


58 


- 8 


17 


70 


68 


70 


70 


69 


- 1 


63 


- 7 


70 


67 


57 


70 


52 


-18 


45 


-S5 


60 


52 


52 


54 


50 


- 4 


43 


-11 


18 


64 


65 


59 


67 


57 


-10 


50 


-17 


56 


59 


50 


63 


50 


-13 


44 


-19 


60 


60 


57 


59 


54 


- 5 


48 


-11 


19 


64 


56 


57 


64 


56 


- 8 


47 


-17 


62 


62 


66 


64 


57 


- 7 


52 


-12 


67 


66 


65 


68 


65 


- 3 


65 


- 3 


20 


56 


55 


51 


61 


50 


-11 


42 


-19 


67 


65 


61 


66 


59 


- 7 


50 


-16 


54 


51 


4S 


52 


42 1-10 


34 


-18 


21 


58 


55 


49 


60 


49 


-11 


41 


-19 


62 


67 


64 


69 


65 


- 4 


60 


- 9 


47 


43 


47 


49 


48 


-1 


36 


-13 


22 


64 


62 


61 


64 


62 


- 2 


59 


- 5 


68 


66 


64 


68 


63 


- 5 


57 


-11 


63 


50 


43 


53 


41 


-12 


34 


-19 


23 


67 


65 


60 


67 


60 


— 7 


54 


-13 


61 


59 


53 


63 


52 


-11 


49 


-14 


56 


53 


54 


55 


54 


- 1 


47 


- 8 


24 


63 


64 


54 


65 


55 


-10 


50 


-15 


67 


65 


64 


67 


64 


- 3 


59 


- 8 


67 


61 


54 


67 


51 


-16 


41 


-se 


25 


66 


61 


58 


69 


57 


-12 


S3 


-16 


60 


64 


53 


64 


54 


-10 


50 


-14 


62 


48 


48 


62 


43-9 


SS 


-19 


26 


48 


52 


48 


51 


48 


- 3 


41 


-10 


64 


62 


49 


65 


48 


-17 


42 


-23 


62 


49 


51 


58 


60-8. 


42 


-16 


27 


49 


53 


45 


54 


43 


-11 


35 


-19 


68 


60 


45 


60 


46 


-14 


41 


-19 


57 


55 


56 


56 


66 





56 





28 


56 


54 


43 


61 


44 


-17 


37 


-24 


59 


61 


59 


60 


59 


- 1 


55 


- 5 


63 


62 


58 


64 


56 


- 8 


60 


-14 


29 


58 


56 


51 


59 


50 


- 9 


43 


-16 


59 


58 


67 


60 


56 


- 4 


48 


-12 


64 


56 


51 


63 


51 


-12 


44 


-19 


30 


64 


62 


58 


65 


56 


- 9 


49 


-16 


53 


53 


53 


56 


50 


- 6 


45 


-11 


64 


64 


64 


64 


64 





62 


- 2 


31. 


















66 


62 


58 


66 


55 


-11 


48 


-18 


67 


61 


58 


54 


58 


+ 4 


52 


- 2 




52.9 


















Means. 


52.1 


49.1 


54.9 


48.6 


-6.3 


42.3 


-12.6 


62.3 


60.7 


55.6 


63.0 


54.9 


-8.1 


49.0 


-14.0 


59.1 


66.3 


54.0 


59.4 


53.1 


-6.3 


47.1 


-12.3 



Uighest and lowest readings are in italics. 



Table 20. — Comparison op Dew-point Readings on the Upland at U and 9 r. M., with Ensuing Minimum 
Temperatures in the Shelter; also of Dew-point Readings on the Marsh at 6 p. m., with Ensuing 
Minimum Temperatures and Differences at Station 4; also Ensuing Minimum Temperatures in Open, 
and Differences at Station 2, Mather. Wis., 1907 — Continued. 









September. 








October. 










Upland, Station 1— 
shelter. 


Marsh. 




Upland, Station 1— 
shelter. 




Marsh. 




l->ay of month. 


Dew-point. 


Mini- 
mum. 


.Station 4— shelter. 


Station 2— 
5 inches, 
exposed. 


Dew-point. 


Mmi- 
mum. 


Station 4— shelter. 


Station 2- 
5 inches, 
exposed. 




6t>. in. 


9 p.m. 


d.p. 
6 p.m. 


Mini- Difler- 
mum. ence. 


Mini- 
mum. 


Differ- 
ence. 


6 p.m. 


9 p.m. 


d.p. 
6 p.m. 


Mini- 
mum. 


Differ- 
ence. 


Mini- 
mum. 


Differ- 
ence. 


1 


n 

01 
48 
54 
52 
53 
57 
58 
49 
49 
51 
54 
59 
61 
64 

63 
67 
69 
54 
5/ 
49 
48 
34 
36 
44 


71 
55 
50 
52 
49 
52 
55 
58 
50 
43 
47 
52 
57 
58 
59 
66 
58 
62 
66 
66 
43 
43 
46 
46 
SI 
33 
42 


70 
53 
50 
52 
44 
41 
54 
56 
40 
38 
45 
48 
50 
62 
63 
67 
.53 
58 
61 
60 
38 
31 
45 
43 
18 
34 
34 
37 
29 
SS 


a 

76 
61 
54 
56 
57 
56 
.t6 
58 
52 
48 
53 
59 
61 
66 
64 
73 
67 
S3 
70 
71 
54 
S6 


s a 

68 - 8 

52 ' - 9 
50 - 4 

53 - 3 

44 -13 
41 -15 
56 
56 -2 
40 ' -12 
42-6 

45 - 8 
43 -16 
47 -14 


s; 


-15 


a 

40 
50 
H 
Si 
41 
50 
48 


35 
51 
46 
51 
44 
44 
51 


o 

33 
52 
46 
41 
41 
44 
50 
23 
40 
35 
35 
29 
25 
22 
44 
36 
39 
24 
27 
28 
19 
40 
30 
29 
28 
19 
34 
17 
32 
37 
37 


39 
52 
54 
56 
36 
49 
55 
44 
32 
43 
42 
30 
32 
26 
36 
39 
50 
36 
26 
36 
28 
41 
45 
46 
35 
29 
35 
20 
35 
40 
41 


33 
« 
43 
37 
38 
42 
44 
22 
40 
31 
35 
29 
22 
20 
44 
36 
33 
24 
22 
27 
18 
36 
26 
25 
25 
18 
34 
16 
28 
37 
35 


- 6 


-11 
-19 

-^ 2 

- 7 
-11 
-iS 
+ 8 
-12 

- 7 

- 1 
-10 

- 6 
-1- S 

- 3 
-17 
-12 

- 4 

- 9 
-10 

- 5 
-19 
-21 
-10 
-11 

- 1 

- 4 

- 3 

- 6 


27 
iS 
36 
27 
27 
34 
37 
16 


-12 


9 


42 -19 
40 -14 
45 -11 


_ 7 


3 


-18 


4 


-?» 


5 


36 
33 


-21 
-23 


- 9 


6 


-15 


7 


55 — / 

56 - 2 
30 -22 
30 -18 
37 -16 
37 -22 
40 -21 


-IS 


8 


14 :;_' 

43 38 

29 30 

30 36 

31 21 


-28 


9. 


33 + 1 


10 


25 
26 
23 
16 
16 
39 
29 
27 
18 
18 
22 
13 
31 
22 
18 
17 
12 
29 


-18 


11 


-16 


12 


- 7 


13 . .. 


-16 


14 

15 

16 

17 

18 . 


60 
60 
66 
52 
58 
61 
59 
38 
35 


- 8 

- 4 

- 7 
-15 

- 5 

- 9 
-12 
-16 

- 1 

- 6 
-U 
-15 

- 7 
-16 

- 7 
-16 


57 
54 
64 
44 
56 
58 
Si 
30 
23 
37 
40 
20 
25 
27 
35 
25 
19 


- 9 
-10 

- 9 
-23 

- 7 
-12 
-14 
-24 
-13 
-13 
-14 
-20 
-17 
-23 
-11 
-21 
-.30 


28 
3S 
44 
52 
46 

go 

33 
29 
34 
48 
42 
29 
23 
32 
10 
29 
40 
41 


26 
40 
42 
44 
24 
26 
35 
25 
33 
27 
30 
31 
24 
39 
It 
25 
38 
42 


-10 
+ S 
-10 
-23 
-18 




- 8 


20 


-14 


21 


-15 


22 


-10 


23 


50 < 44 


-23 


24 


54 
40 
42 
50 
46 
46 

4ri 


43 
25 
35 
34 
39 
30 

:/ 


-28 


25 


-18 


26 

27 


-17 

- 6 


28 

29 

JO 

31 


44 40 
38 38 

46, 39 


10 -10 
26 - 9 
35 - 5 
29 1 -12 




1 










Means 


53.1 


50.9 


47.1 


56.3 


46.6 


-9.7 


40. 4 1 -15. 9 


37.7 


35.3 


33.4 


39.0 


31.4 


-7.6 


25.3 


-13.7 



Highest and lowest readings arc in italics. 



88 



Table 20". — Monthly .\nd Season.\l Mean.s — Dew-point .a.nd Ensuing Minimum Temperatures, Mather 

Wis., 1907. • 





June. 


July. 


-Vugust. 


Septem- 


October. 


Means. 


Upland: 
■ Station 1, shelter- 
Dew-point. 


52.9 
52.1 
49.1 


62.3 
60.7 
55.6 


59.1 
56.3 
54.0 


53.1 
50.9 
47.1 


37.7 
35.3 
33.4 


53.0 


9p in . 


51.1 




47.8 






Marsh: 

Station 4, shelter- 
Dew-point. 


54.9 
48.6 


63.0 
54.9 


59.4 
5:!.l 


56.3 
46.6 


39.0 
31.4 


54.5 




46.9 








- 6.3 


- 8.1 


- 6.3 


-9.7 


- 7.6 


— 7.6 






Station 2, 5 inches. exposed- 


42.3 
-12.6 


49.0 
-14.0 


47.1 
-12.3 


40.4 
-15.9 


25.3 
-13.7 


40.8 


Difference 


—13.7 







Dew-point readings at Berlin. — Observations of dew-point and the ensuing minimum air 
temperature made at Berlin in 1906 confirm the results obtained at Mather. Even though 
the ah- was saturated in the early evening and dew formed rapidly, the temperature often fell 
steadily in spite of the large amount of latent heat liberated by the condensation of water vapor 
into dew, as on the night of September 23-24. Of course the fall in temperature was not so 
rapid when the humidity was high and the dew was forming fast, but there was, nevertheless, 
usually a steady fall on clear nights. The moist condition simph^ tended to lower the rate of 
cooling, and it is probable that the radiation of heat from the dewdrops themselves was great. 
Aside from reference to the tables compiled from Mather observations, a few comparisons made 
at Berlm are given below between the dew-point in the evening preceding nights of frost with 
the ensuing minimum temperature. 



Dew-point 
previous 
evening. 



Minimum 
temperature, 
shelter read- 
ings. Sta- 
tion 1. 



Minimum 
temperature, 
5 inches. Sta- 
tion 5. 



September 5 . . . 
September 14. . 
September 24. . 
September 27. . 
September 28.. 
September 30. . 
October 1 

Averages 



28 
29 
29 
24 
28 
23 
19 



47.9 



37.9 



25.7 



In a dry section at some little distance from water and bog land there may be some con- 
nection between the dew-point and the ensuing minimum temperature. When a high degree 
of moisture is present in the air as over a moorlaml, and when the temperature falls ra])idly in 
the evening, as it usually does on clear nights, the point of saturation is reached in a brief 
period. 

Fog aver marshes and low temperatures. — Fog, even though light, has been supposed by 
some to be a preventive of frost, but this is not quite true; in fact, fog may form over a bog 
on almost am^ clear cool nigiit following a warm day when the soil has been heatetl and the air 
for some distance above the surface highly cliarged witli water vapor. The rapid radiation 
from the surface and humid air on a clear night after a warm day carries the temperature 
below the dew-point, and fog is immediately formed. It is often said that the formation of 



89 

fog under such conditions indicates a rapid fall in temperature, and cranberry growers are 
accustomed to look for a frost when on a clear night light fog forms over the moorland. On 
such nights the radiation of heat from the particles of fog serves even to lower the tempera- 
ture of the air. Of course, the radiation of heat from the ground is more or less arrested as the 
fog increases, but it is surprising what little effect fog seems to have in preventing low night 
minimum temperatures in the bogs. 

Special observations on critical nights at the Berlin marsh, September, 1906. — Personal 
observations in the bog at Berlin, 1906, during several nights when low temperatures occurred, 
convinced the writer that high humidity and even fog have hardly any effect in retarding the 
fall in temperature. Even when the bog seemed reeking with moisture, the temperature fell 
steadily. Often during critical nights, observations of special conditions were made nearly 
every hour in certain portions of the marsh. There was little opportunity for this kind of 
work until September, as the temperature during the summer was far above the normal. 

On August 27 the exjiosed minimum temperature at Station 5, in tlie "ferns," at the 5- 
inch height was 30.5°, while near the surface at the same place the mmimum was 32.2°, and 
in the shelter at Station 1 it was 45.5°. No frost, however, was observed that morning at any 
point in the l)og. On the morning of September 5 the minimum temperatures were 28.3° at 
the 5-inch height and 32° at the surface at Station 5, and 42° in the shelter at Station 1. Again, 
no hoar frost was observed, although the exposed minimums registered several degrees below 
the freezing point. The ferns, however, were damaged by tliis low temperature, as they began 
to wither immediately afterwards, and some slight damage was noted in the neighboring low- 
lands outside the marsh. Occasionally light frost may occur in the bogs and pass unnoticed, 
disappearing very early in the morning, and the wiiter has known of several instances where 
frost was not observed, although damage to vegetation gave evidence of its occurrence. While 
these minimum temperatures, of course, do not represent the temperature of the air, yet, even 
if they represent approximately the temperature of the plants and vines, hoar frost might be 
expected when these readings fell a few degrees below freezing. The first date on which frost 
was actually observed at Berlin was September 14, under conditions quite similar to those of 
the 5th. The shelter minimum at Station 1 was 41.3°, while the minimums at the 5-inch 
height and at the surface at Station 5 were 28. S° and 32.6°, respectivch*. The morning of the 
14th was clear, but with fog over the marsh. (Fig. 6.) Light frost was observed first on the 
wooden car tracks at the intersections where tlie rails had been spliced, but not on the main 
portions of the track, or on the cross-ties lower down. (Figure 17 sjiows the tracks and 
cross-ties.) These splices were about 4 inches above the surface of tlie marsh, and afforded a 
better opportunity for radiation. A jieculiar phenomenon was noticed at Station 5: The 
maximum and the minimum thermometers at the 5-irich height were found completelg cockered with 
frozen dewdrops, dew having been deposited sometime during the night, after which the temperev- 
ture fell to the freezing point. The thermometers resting on the surface were absolutely free from 
frost or moisture of any hind. This is a most striJcing example of safety at tlie surface and frost 
and possibly destruction a few inches above. Some frozen dewdrops were also found on the tops 
of the splices already referred to. Ordinarily, dew formed on vines and other objects at an 
elevation of a few inches above the ground sooner than at the immediate surface, doubtless 
because at that elevation there was no direct connection with the warm ground and the radia- 
tion was freer, the dew-point was more readily reached, rather than because of any difference 
in the amount of moisture. A light frost occurred at Mather and Cranmoor on September 14, 
as well as at Berlin, temperatures below freezing being reported in all the Wisconsin bogs. The 
frost on the 14th would probably have been more severe had the soil been colder; but it was 
comparatively warm, because of a hot wave of several days jireceding the cool spell. On the 
14th considerable differences prevailed between the temperatures on the uplands and m the 
bogs, as is usual under such conditions. 

Light frost was again observed at Berlin on September 24, freezing temperatures being 
recorded at both exposures at Station 5, but the temperatures were not so low at Cranmoor 



90 

and Mather, tlie sk}' there becoming overcast before midnight. The Berhn marsh was c|iiite 
wet from recent rains, especially in tlie east poition wliere tlie water was almost up to the 
surface. The water had been partially (haiiied from llie west portion, but it was still wet, 
especially on low ground. In tlie liig ditcii near Stations 2, .3, and 4, the water was but 2 to 3 
mches below the surface. The sky was ck'ar (kiring the entiie night. About 7 p. m. on the 
23d fog was first o])served along the main ditch; after midnight the fog increased and spread 
over tlic bog, and by 3 a. m. it was very dense. The whole marsh seemed to be reeking with 
moisture. The relative humidity was 100 per cent continuou.sly after 10 p. m., yet the tempera- 
ture fell rather uniforndy until I a. m.; then after remaining stationary about an hoiu' it rose 
gradually. In tlie morning frost was observed on most of the wooden car tracks, especially 
wliere they were situated away from tlie water. None was observed on the cros.s-ties restmg 
on the surface of the bog, and while frost was seen generally on the tracks, it was more pro- 
nounced on tiie edges and on the upper side of the splices covering the joints of the rails, where 
radiation was freest. In other words, frost was heavier at a shglit elevation on account of 
freer radiation than at the immediate surface, this being c<msistent with the readings of the 
thermometers. The minimum temperatiu'C on top of the tracks was 27°. A thermometer 
placed in the vines, a few inches above tlie surface and just touching three berries, registered a 
minimum of 31°. The instrument and the exposed berries were covered with frost, but the 
berries near the ground were not frosted. Frost was also observed on the leaves, vines, and 
grasses, but no damage as a result was afterwards Tioticeil. A thermograph placed in the 
''ferns" where the vegetation had been trampled was covered with frost and registered a 
minimum of 26°. Invariably lower minimums were found in sections that had been trampled 
than in the unjncked sections where the vines and grasses stootl upright. 

Frost occurred in all marshes on September 27 and 28, it bemg heavy at Berlin on the 27th 
and light on the 2Sth, increasing cloudiness after midnight of the 27th preventing the frost 
from becoming severe. Dew did not form rapidly on the first night. At 10 j). m. the siielter 
thermometer at Station 1 registered 50° and the dew-point was 46°. The marsh was com- 
paratively dry, in strong contrast with the moist conditions of a few days previous. The 
shelter thermometer at Station 1 fell from 50° to 45° between 10.30 p. m. and 11 p. m., but there 
was no sign of frost at the latter hour; the tracks were dry and the dew-point was 43°. Some 
fog appeared about midniglit, the temperature continued to fall steadily, and frost was observed 
first on tiie metallic covering of the thermograph in the "ferns'' at 1 a. m., where the tempera- 
ture had fallen to 28°. A few minutes later it was observed on the splices of the car tracks 
near by, and by 2 a. m. on the entire ti'ack. At that time tlie temperature on to]) of the track 
was 27° and on the cross-ties 31.5°. At 4 a. m. these readings were 24° and 30°, re.spectively. 
A thermometer placed in the midst of berries about 5 inches above the surface recorded 28°, 
and another about an inch above the surface, 29°. Tlie tliermometer at the 5-inch height in 
the "ferns" at Station 5 on the morning of the 27th registered a minimum of 24.4°. Frost 
was again most noticeable on the marsh where the vines had been trampled and hardly notice- 
able where they stooil upright. Although the berries were covered with frost, it had evidently 
not penetrated the skin, and no resulting damage was ai)parent later. The frt)st on the 2Sth 
was light in the various sections. 

The mt)st important frosts of the autumn season of 1906 occurred on September 30 and 
October 1. The barometer was high in the marsh region on these two nights, as on previous 
occasions when low temi)eratures occurred. The weather maps showing the distribution of 
pressure will be discussed later. At Berlin, on tiie 29th, the temperature did not fall rapidly 
until lat(! in the evening, as the sky was covered with clouils, wliich did not disapi)ear until 
after 10 p. m. The temperature then fell rapidly, reaching a iiuninuun of 23.2° in the "ferns" 
at Station 5 on tlie marsh. Ileav/ frost was general over the entire bog, hut the berries were 
apparentlg not frozen, and no resulting damage was noticed, although flowing was not resorted to." 

"The berry when green can usually withstand a temperature in "the open" of about 28°, and when fully 
inalurcd. of 23° or 24°, dopendini;, of four.se, upon the duraticMi of the critieal tomperalure. 



91 



On the morning of October 1 tlie most severe frost of the season occurred, the temperature 
in the "ferns" at the surface being 23° and at the 5-inch lieight 19°. On the wooden cross- 
ties of the track the minimum was l.S°, and 4 inches lower at the surface it was 22°. A ther- 
mometer j)hiced in tiie midst of a bunch of berries about 5 inches above tlie surface registered 
22°, and another instrument 1 inch above the surface, between the berries, registered 24°. 
Tlie shelter minimum at Station 1 was 29.4°, while a thermometer on a board walk on hard 
land near Station 1 , where heavy frost occurred, registered 22.8°. The temperature of the water 
in the reservoir at daybreak was 53°, and in two small ditches it was 37° and 39°. All the 
berries remaining unpicked were frozen hard as marbles, with the exception of those near the 
surface of the dry sanded section wiiere the miuimuni temperature was 35.8°. As the berries 
thawed out, however^ only 

about 33 per cent of them SEPTE MBER- OCTOBE R 

showed injury. In other 29ih. 30th. (St. 

words, about one in three nOOn md\. 0000 mdt. 00 OH 

was soft and semi-transpar- 
ent, and the other two were 
firm and apparently in good 
condition. The berries that 
were exposed directly to the 
sun's rays in the morning 
thawed out rapidly and 
showed the effects of the 
frost, there being an unusual- 
ly rapid rise in temperature 
on the morning of October 1. 
(Figure 28 shows the thermo- 
graph traces in shelter and 
on the marsh.) The major- 
ity of the berries were located 
below the thick growth of 
vines and other vegetation, 
so that the sun's rays did 
not directly strike them and 
warm them rapidly, and 
the thawing was, as a result, 
gradual. If the morning of 
October 1 hail been cloudy, 
permittmg the slow thawing 
out of the uppermost berries, 
it is possible that the entire 
crop might have escaped serious injury. Other fruits as well, after having been frozen, fail 
to show the effects of frost when the thawing is gradual. 

Effect of frost on the cranheiry. — The resisting power of the cranberry increases steadily as 
it matures. In the autumn, when colored anil fully matured, the berry can withstand a tempera- 
ture many degrees lower than when green and unripe. As it ripens it not only colors but the 
skin thickens, and its content changes somewhat and offers an increased resistance to frost. 
Growers state that sometimes, although no danuige is apparent after freezing weather, the berry 
thus exposed is chilled, and if ])laced near a fire will become semi-transparent and soft, resembling 
somewhat a baked apple, and show all the characteristics of having been frozen. An experi- 
ment was made on the morning of Scptend)cr 30 by placing some of the chilled berries near a 
fii-e, but no deterioration was detected in any of them. It is said that berries exposed to frost 
on two successive nights, after apparently having escaped injury the first night, wQI on the 
morning following the second night exhibit symptoms of being frozen, even though the cold 
on the second night is not as severe as on the first. It is supposed that the low temperature 




iN FERNS 
IN SHELTER 



Fig. 'iS.— Berlin, Wis. 
Temperature curves in shelter Station 1, and in open in the ferns station !<, noon 
September 29 to noon October 1, 1906. Uncorrected rearlings. 



92 

of the first night starts a certain disintegration in the cranberry which is completed during the 
second night. • 

According to Prof. E. R. Lake," low temperature congeals the watery part of the cell 
sap and also the intercellular water content of the plant. Within certain limits this is not or 
may not be injurious, providing the protoplastic contents of the cell are able to absorb the 
water and do this before the cell structure collapses as a result of insufficient cell turgor. 
Frequently the frosting of plants is followed by a sudden rise in temperature, in which case 
much of the water which was part of the cell sap in the normal condition of the plant escapes 
through the cell wall into intercellular spaces, or even from the plant entirely, and thus the 
protoplasm of the cell being unable to assume its normal condition becomes disorganized and 
decomposition follows.* 

Disadvantage from rejiounng. — It was possible to reflow only a portion of the Berlin marsh 
previous to frosts, and reflowing was seldom attempted there, as the drainage was poor, 
and the water could not be drained off quickly. As the picking season advances the water 
becomes colder and it is consequently more trying on the cranberry pickers. When a marsh 
has been reflowed the pickers on the day following seldom start work until noon, in order to 
avoid the dampness, as they object to working in a wet marsh and sometimes refuse to do so. 
Where the drainage is poor, the cranberry grower has sometimes to decide between leaving his 
marsh dry and risking the damage from frost, or reflowing and chancing the desertion of his 
pickers. In either case, the harvest is affected. It is important that as many pickers as 
possible i)e held until after the crop is gathered. On the Appleton marsh at Mather there is 
usually ample water supply and fairly good drainage under ordinary circumstances, and it is 
invariably flooded in anticipation of frost. Aside from the discomforts caused to the pickers 
working in a wet marsh, frequent reflowing softens the terminal buds, so that they are easily 
bruised b}- the pickers, and the crop of the following j^ear is seriousl}^ affected as a consequence.'' 

Special data in connection vnth forecasting frost in the cranberry marshes. — The subject of 
local conditions in the bogs having been treated in detail, it is important that the discussion now 
turn to the relation existing between the temperature in the bogs and the general weather 
conditions throughout the country, as shown by the daily weather maps. Reference now will 
be made to ma])s of various types, especially during the years 1906 and 1907, which have pre- 
ceded critical conditions in the Wisconsin bogs, in order that assistance may be afforded the 
forecaster and the cranberry grower in determining the probability and severity of frost. 

Discussion of daily weatlier maps and local conditions in connection with frosts in the Wis- 
consin bogs in 1906. — Observations in the bogs during the season of 1906 were of course incom- 
plete, although some data from Mather, Berlin, and Cranmoor are available from May 21 to the 
end of the season. It may be well now to refer tothe severe frost which occurred on May 28, 
and the light frosts on June 11, 12, and 13 of that year, in connection with the weather maps 
issued at that time. 

The weather map of May 27 shows a storm central over the southern portion of Illinois 
and Indiana, and a high-pressure area in Manitoba, encircled by a 30.2-inch isobar, with temper- 
atures in the Dakotas and at Moorhead of about 40°. General rains prevailetl throughout 
Wisconsin on May 27, with strong northeast to north winds. The maximum temperatures in 
shelters at Berlin, Mather, and Cranmoor were, respectively, 47°, 54°, and 53°. On the morning 
of the 28th the storm center had passed to the Middle Atlantic coast, while the high-pressure 
area had moved to the western Lake Superior region, a ridge extending southward over the 
Middle States. The pressure in the Wisconsin moorlands was approximately 30.15 inches, and 
the wind was light northeast with clear weather. The minimum temperatures were 21° at 
Mather, 29° at Berlin, and 28° at Cranmoor, with severe frosts at all three marshes. 

The frosts of June 11, 12, and 13, 1906, were the only frosts which occurred during that 
month, and while they were not severe they nevertheless occurred at a critical time, and were 

a Prof, E. R. Lake in Oregon Climate and Crop Bulletin, July, 1900. 

6 Professor A. G. McAdie states in Climatolofiy of California (Bulletin L, U. S. Weather Bureau) that fruit 
growers in California have found it advantageous to interpose some screen early in the morning between the sun's 
rays and the frosted fruit. 

cin many bogs the berries are gathered tjy raking instead of pirking. 



93 

remarkablp for their duration. The weather maps for June 10, 11, 12, and 13 fui-nish an expla- 
nation of these persistently low temperatures. On the morning of June 10 the barometer was 
low in both the northeastern and southeastern portions of the country, and a high-pressure 
area was centered at Winnipeg, where the barometer was 30.2 inches and the temperature 
below 50°. The HIGH moved eastward over the northern Lake region, steadily inci-easing in 
magnitude. On the morning of the 13th it reached from the .St. Lawrence to the upper 
Mississippi Valley, with the center in Ontario, and encircled by a 30.4-inch isobar, the pressure 
in the bogs being about 30.25 on the 11th and 30.30 on the 12th and 13th. There was but 
little baroinetric gradient in the moorland sections on the mornings of June 11, 12, and 13; the 
wind was light from the northeast, and the weather clear both day and night. The appended 
table shows the maximum shelter temperatures on June 10, 11, and 12, and the minimum 
temperatures on the bog on June 11, 12, and 13. 





Maximum temperatures in 
shelter. 




Minimum temperatures on 
bog.a 




Mather. 


Berlin. 


Cranraoor. 


Mather. 


Berlin. 


Cranmoor. 


1906. 
June 10 


74 
72 


• 

71 
66 


70 
68 
68 


1906. 
June 11 


28 


35 
33 
33 


35 






28 


34 




71 67 


June 13 


26 


31 











a Xt Berlin and Cranmoor the minimum thermometers were not at this time located at the coldest places on the marshes. At the coldest 
point the temperature ordinarily had to fall to 28" or 29° before frost was observed. 

Frost was observed in the three cranberry marshes and generally throughout the mooi'- 
lands on these days. The minimum temperature readings at Mather better represent the 
general temperature conditions than those at Berlin and Cranmoor, as the thermometer readings 
at the latter place were affected by water from reflowing, and moreover tlie thermometer at 
Berlin was not at that time located in the "ferns," the coldest point on the bog. The Bei'lin 
minimum readings above are for Station 2, which it was later found averaged 3° to 4° higher 
than in the "ferns." These frosts disappeared before sunrise each morning as the temperature 
rose. 

No soil observations are available to show the temperature of the soil in the marshes at 
that time, as the soil thermometers had not been installed. However, there is no doubt that the 
temperature of the soil was low, and had much to do with the occurrence of the frost. There 
had been no unusually warm weather in the season of 1906 previous to June 10 that would serve 
to heat the soil to any great extent. It was found in the observations of 1907 that there was an 
irregular increase in soil temperature from the beginning of the season to about the middle of 
August. In that year the soil temperatures at the 3-inch depth in the peat bog at Mather on 
the corresponding dates in June were not above 52.5°, as compared with a maximum of 69.5° 
on August 12. During the middle and late summer, when the maximum air temperatures in 
the shade reach 70° or higlier, there is ordinarily little probability of frost the ensuing night, 
because under such conditions the soil is heated considerably beneath the direct rays of the sun. 
At other times during the season maximum temperatures as high as 75° may be succeeded by 
frost. Frost very seldom occurs in the summer montlis on a night following a clear sunshiny 
day, and it can occur under these circumstances probably not later than June 15. Had the 
weather conditions of this period, as far as pressure, clear sky, and maximum temperature are 
concerned, occurred (hiring July or August, frost would not have formed, because the ground 
would have been warm enough to prevent the temperature at its surface from falling to the 
freezing point. 

During this period of three days in 1906 several o( the growers retained the water over 
their marshes both day and night, or at least up to the surface, thus saving the supply of water 
which might otherwise have become exhausted. Unless the cold is expected to continue, growers 
after reflowing begin to drain off the water at daybreak, because if it remains on the bog during 



94 



SEPTEMBER, 1906 

23rdi. „ 24.-th. 

noon mar. noon 



a warm sunsliiny clay there is clanger of scalding the berries and vines. No additional frosts 
occurred at Mather in the summer of 1906, and the first frost in the autumn was on September 1-i. 
Tills first frost at Mather in September, 1906, was a light one. The pressure at the time 
was 30.24 inches, rising, and the preceding day, the 13th, had been partly cloudy with 
77 per cent of sunshine, while the night had been clear, there being, however, a light fog 
during the early morning of the 14th. The temperature had been steadily falling since the 
11th, a maximum of 90° having occurred on that date. On the 13th the highest temperature 
in tlie shade was 6S°, and the temperature of the soil had been much reduced; in fact, it was 
lower at 6 p. m. at all stations on the bog than on any previous evening in September. At the 
time of the minimum temperature of 31° on the 14th there was an absolute calm on the bog. 
A fresh breeze had been blowing from the north the day before, partially evaporating the mois- 
ture produced by the rain which had fallen on tlie 12th, and as a consequence lowering tlie 
tempeiature at the surface of the soil. 

Reference to the weather map of the 13th shows that the high-pressure area was then 
centered over the eastern portion of South Dakota, the center being inclosed by a 30.2-inch 

isobar with temperatures as low as 40°. The ba- 
rometer rose rapidly in the moorland sections dur- 
ing the day, the center of the HIGH moving directly 
eastward to the Lake Superior region, where the 
pressure was 30.4 inches on the morning of the 14th. 
Had the soil been colder, the general conditions pre- 
vailing on the 14th would have caused a more severe 
fi-ost ; for, although the temperature of the soil had 
been lowered, as already stated, it had previously 
been very warm as a result of the hot wave of sev- 
eral days' duration. 

While frost occurred in the marsh at Berlin on 
the morning of September 24, the lowest "exposed" 
teni))erature at Mather was only 38°. The condi- 
tions seemed to be very favorable for low tempera- 
ture in all moorland sections, but the clear weather 
at ]\Iather on the night of September 23 was fol- 
lowed by increasing cloudiness before midnight, and 
the temperature, which had previously been falling, 
rose until 2 a. m., and then remained nearly sta- 
tionary until 5 a. m. of the 24th. (Figure 29 shows 
the thermograph traces in shelter. Station 1, at each 
marsh.) The area of high barometer passed east- 
ward with its center over Lake Superior, and was 
followed by a low-pressure area in the far Xorthwest. A light wind from the north prevailed 
at Berlin, which was nearer to the center of the high, while at Mather, located farther west, the 
wind had shifted to the southeast with increasing cloudiness under the influence of the LOW 
in the northwest, referred to above. 

The first severe frost at Mather in the fall of 1906 occurred on the morning of September 27, 
and this was followed by another frost on the 28th. In both cases heavy dew was observed 
on the uplantls, but no frost. Frosts, however, were general on both these dates in all the Wis- 
consin cranberry marshes. The barometer at Mather on the morning of the 27th was 30.36 
inches, rising, and 30.16 inches on the morning of the 28th, falling. Tlie night of the 26th-27th 
was clear, while the night of the 27th-28th was partly cloudy, and, probably because of the par- 
tial cloudiness, the mininuun temperature, 31°, on the 28th was not as low as the mininuan 
temjierature of the 27th, 28°. Rain had occurred on the night of the 25th-26th, followed by a 
fresh wind during the daytime of both the 26th and the 27th. The maximum temperature 
in the sluulc on the 26th was 68°, and 69° on the 27th. Of course, this was late in the season, 




BERLIN 
MATHER 



Fig. 29.— Mather and Berlin, Wis. 

Traces of thermograph in slielter from uocm, September 23 t 

noon. September 24, I90G. 



95 

and witli clear weather the maximum temperatures would have been much higher if the days 
had been longer. The soil temperatures had been steadily falling, and on the 28th the lowest 
6 p. m. readings of the month up to that time were recorded. The center of the high-pressure 
area on the 26tli was well to the north, as shown by the weather map, with freezing temperatures 
in the British Northwest. The temperature at Moorhead, Minn., on the morning of the 27th 
was as low as 38°. 

Heavy frost again occurred in all the Wisconsin bogs on the mornings of September 30 
and October 1. Light rain had occurred at Mather September 28, and a fresh wind from the 
north prevailed during the daytime of the 29th, with cloudy weather and 67 per cent of sunsliine. 
The maximum temperature on the 29th in the shelter at Station 1 at Mather reached only 67°. 
The barometer, which was only slightlj^ above normal on the morning of the 29th, 30.04 inches, 
rose steadily during the day and night, reaching a heiglit of 30.42 inches on tiie morning of the 
30th. Frost began to appear in portions of the Mather marsh at 10 o'clock on the night of tlie 
29th, and it was general over the entire mar^i on the following morning, the minimum tempera- 
ture at Station 2 over the moss being 25°, and 32° Ln the shelter at Station 1. On the morning 
of the 30th light fog lay over the marsh. Although the weather was clear on the 30th, the maxi- 
mum temperature in the shade reached only 65°, and the soil temperature remained low on the 
29th and the 30th. The exposed minimum temperature on the moi'ning of October 1 at Station 
2 was 25°. 

Tlie weather maps of September 29 and 30 and October 1 should be studietl in connection witli 
these frosts. An area of high barometer of great magnitude covered the Northwestern States, 
the 30.4-inch isobar inclosing the Dakotas and the eastern portions of Montana and Wyoming, 
and freezing temperatures were reported in North Dakota. The movement of the HIGH was 
directly eastward, reacliing the western Lake region and Upper Mississippi "S'alley b}- the morning 
of the 30th, and the St. Lawrence Valley by October 1. On the latter date the barometer 
remained high over Wisconsin, as a ridge reached, westward over the Lake region from the 
St. Lawrence Valley. A tropical storm, which had on the 27th caused great destruction at 
Mobile, was pushing northward through the interior of the country, and had advanced as 
far as St. Louis by the morning of the 29th. The high pressure area, however, moving directly 
southeastward, crossed its path and forced the LOW backward to the Gulf coast. The sliift- 
ing of these areas brought down the cold air in a great mass over the Middle States on the 
morning of September 30. 

Discussion of daily weather maps and local conditioi}s in connection with frosts in the Wis- 
consin hogs in 1907 . — Table 21 has been made quite comprehensive in order to show all the 
weather conditions that may be needed in connection with the study of the occurrence of frost 
in the bogs at Mather during the season of 1907. It is intended to supplement the tables which 
have preceded, and may be used in connection with Mather observations of various kinds. The 
barometric pressure, rainfall, wind velocity and direction, state of weather both day and night, 
and the amount of sunshine are most important in addition to temperature data. 

In 1907 the observations began on May 12. During the balance of that month there were 
eight days on which the temjjerature "in the open" at Station 2 fell to freezing or below. On 
May 19, although the temperature was as low as 28°, no frost was seen, and on the 27th, when a 
temperature of 27° occurred, none was seen, although thin ice was observed early in the morning. 
A so-called "dry freeze," however, is often more dreaded b}' the cranberry grower than a heavy 
hoar frost. Nevertheless, it is evident that these "exposed" minimum temperatures at Station 
2 were considerably lower than the actual temperature of the air. Low temperatures are so 
common in the Wisconsin bogs durmg the month of May and the first decade of June that it 
should not be necessary to make any special reference to the weather maps for that period. 
During the spring and early summer comparatively low temperatures often occur when the 
barometer is below normal, but never in midsummer. The lowest temperatures, moreover, 
almost invariably occur with high barometer. On Maj^ 20 and 21, for instance, when tempera- 
tures of 18° and 21°, respectively, were reported, the pressure was 30.30 inches and 30.32 inches. 
51936°- Bull. T— 10 7 



96 

The frost of June 8 was severe, the minimum temperature at Station 2 being 28°. The moss 
on tlie bog was frozen hard in places, an^i there was a heavy coating of frost on the instruments 
and vegetation. The air over the bog was calm, and the wind on the upland, 7 miles an hour 
from the north. The minimum temperature in the shelter at La Crosse, Wis., was 48°. The 
weather the day before, June 7, was cloudy and threatening, with a maximum of 64° in the shade. 
The unsettled conditions cleared away at 9 p. m and the pressure increased. On the morning 
of the 8th the center of the high-pressure area was over the Lake Superior region, and the barome- 
ter on the bog was 30.04 inches. Although the temperature was as low on the 1st and the 6th, 
only light frost was observed on these dates. 

The last frost in June was on the 14th. On the morning of the 13th an area of high pres- 
sure was located over the Lake Superior region, the highest reading being 30.16 inches, at Port 
Arthur. This area seemed to spread southward, and had settled over Wisconsin by the morning 
of the 14th, with a pressure at Mather of 30.10 inches. The maximum temperature in the shelter 
at Station 1 was 75°, about 5° above the average maximum that may be expected on days pre- 
ceding frost. There was a quick recovery in temperature during the daytime of the 14th, the 
maximum reaching 81°. The lowest temperature at Station 2 on the 14th was 31°, while the 
minimum at La Crosse was 50°. 

On July 2 the lowest temperature at Station 2 was 29°. There was a heavy dew in the 
morning, but no frost was observed. Light frost may have occurred in portions of the marsh 
before daybreak; if so, it disappeared before the observer reached the bog. The sky on the pre- 
vious night was clear and the pressure on the morning of the 2d was 30.10 inches. A calm 
prevailed on the bog, and the wind velocity and direction was 5 mUes, north, on the upland. 
The minimum temperature at La Crosse was 50°. A fresh northwest wind had prevailed the 
the day before in the bog region, accompanied by sprinkles of rain, while the maximum tem- 
perature in the shade was 71°. Reference to the weather map of July 1 shows a generally 
unsettled condition from the Lakes westward to the eastern slope of the Rockies. The pressure 
in the latter section was 30.14 inches and this gradually shaded off to a low pressure of 29.70 
inches in the St. Lawrence Valley. The barometric gradient was not decided, but the condi- 
tions prevalent on the 1st were sufficient to cause fresh northwest winds. The lowest tempera- 
ture reported from any station in the Northwest was 44° at Minnedosa. On the morning of 
the 2d the high-pressure area reached in a wide belt from the Lake Superior region southwestward 
over Wisconsin, Iowa, and Nebraska to Colorado; and on that morning in the bog region the 
wind had fallen to practically a calm. 

No freezing temperatures were observed again at Mather until September 9 and 10, when 
30° was recorded at Station 2, but no frost was noted on either of these dates. On the weather 
map on the morning of the 8th appeared a seemingly typical condition — a low-pressure area over 
Lake Michigan and a high-barometer area encircled by a 30.30-inch isobar over the northern 
Rocky Mountain region. Temperatures were as low as 38° at Moorhead and Devils Lake. 
During the ensuing twenty-four hours the HIGH moved slightly southeastward, retaining its 
magnitude, but the LOW over the Lake region moved but little and lost force, the pressure in 
the center bemg 29.90 inches, as compared with 29.78 inches the jjrevious morning, September 
8. Frost was reported on the morning of September 9 from the regular Weather Bureau sta- 
tions at Devils I^ake, Bismarck, Williston, and Havre, with minimum temperatures of 36°. 
An unusual change in the general conditions occurred during the 9th, as both the high and the 
low pressure areas moved directly southward. Frosts were still prevalent in the Northwest, 
with persistently low temperatures, but cloudiness prevailed over the bog region on the nights 
of September 9 and 10 and prevented any severe freeze. While the temperature was 30° on 
the bogs on both these dates, readings of 45° and 46°, respectively, were reported from La Crosse. 
The maximum temperature in the shade at Mather was 65° on the 8th and 68° on the 9th. 
The barometer on the two mornings was 30.02 inches and 30.04 inches, respectively. There 
was but 50 per cent of sunshine on the 8th, the day being partly cloudy, and as a consequence 
the soil was not heated materially. The general weather conditions in the Northwest seemed 



97 

to be ideal for producing severe frost in the Wisconsin bogs on both the 9th and the 10th, and 
it was prevented only by the cloudiness. 

A temperature of 30° was again recorded over the moss at Station 2 on September 21, but 
no frost was observed. The barometer was just normal, 30 inches, and some cloudiness had 
occurred during the previous night. The maximum temperature on the 21st was only 62°, but 
the temperature fell rapidly after sunset, a minimum of 23° being recorded over the moss at 
Station 2 on the morning of the 22d. There was a well marked low pressure area over Lake 
Superior on the morning of the 20th, the barometer being 29.50 inches at Marquette, while a 
liigh encircled by a 30.20 inch isobar covered the northern Rocky Mountain region. The HIGH 
moved directly eastward, so that on the morning of the 21st it extended from the Rocky Moun- 
tains to the Missouri River valley, and killing frosts and freezing temperatures were reported 
from North Dakota. Tliis area then moved southeastward during the next twenty-four hours, 
and on the 22d it was centered in Missouri, the highest barometer being at Kansas City, 30.18 
inches. The barometer at Mather on the morning of the 22d was 30.08 inches. Wliile the 
minimum temperature over the moss at Station 2 was 23°, in the shelter at Station 1 it was 31°, 
and at La Crosse, 38°. On the 21st on the moorlands partly cloudy weather prevailed with 70 
per cent, of sunshine, and a fresh northwest wind which died away to a calm on the bog by the 
morning of the 22d. Killing frosts were general on the mai-shes on the 22d; some frost was 
observed even the night before at 10.30 p. m. 

Killing frosts were again reported in the bogs on the 25th, 26th, 29th, and 30th, and light 
frost on the 27th, as two areas of high pressure, one after another, pusheil fron: the northern 
Rocky Mountain region southeastward over the central valleys. The temperature was so low 
within these areas that general frosts occurred on the uplands of the Middle States on September 
25, 26, and 30. The nights, of course, were gradually laecoming longer and the soil was growing 
colder, making the occurrence of frost more likely. The minimum temperature at Station 2 on 
the morning of the 30th was 19°, and frost was very heavy. The pressure was 30.32 inches, the 
wind very light from the west, and there had been only 33 per cent of sunshine the day before. 
The frosts of the 25th and 26th occurred also with high pressure, but on the mornings of the 27th 
and 29th, the barometer was but slightly above the normal. The minimum temperature at 
La Crosse on September 30 was 36°. 

The cranberry mai-sh at ^Mather was reflowed in anticipation of these September frosts, and 
the sections that had not been picked were reflowed from time to time during the first half of 
October. Frosts, of course, were quite frequent during the month of October; so frequent, in 
fact, that it is not necessary to make any special study of these conditions in connection with the 
Aveather maps. Picking usually terminates early in October, and frost warnings are therefore 
not needed. The observations, however, were continued until the end of October, in order to 
complete the meteorological record for the season, insuring data up to the tune that frost enters 
the ground. Moreover, after the crop has been picked, the observations were free from the 
complications usually arising from reflowing. The temperature over the moss at Station 2 
during the month of October fell below freezing twenty-four out of the thirty-one days, the 
lowest temperature being 10° on October 28. On that date, the minimum temperature at La 
Crosse was 22°. The first ice was noted on October 8, and snow fell on the 19th. Damp ground 
was frozen on the 18th, and ice in the main reservoir was noted on the 21st, the minimum 
temperature on the latter date being 13°. 

From a studj' of Table 21, it will be observed that frosts occurred usually on clear and com- 
paratively cahn mornings, with pressure above the normal. While high barometer is appar- 
ently not essential in the spring and early summer and in the autumn, frost never occurs during 
the warm months of July and August, and the firet decade of September, wlule the ground is 
warm, except with a pressure considerably above the normal. Table 21 has been made compre- 
hensive in order to afford o])portunity for those interested to study in detail the subject of the 
temperature conditions in the bogs. 



98 



Table 21.^Daily \Ve.\ther Conditions, Mather, Wis., 1907. 

ilAY. 





Barometer — Rising 
(R), falling (F), sta- 
tionary (S). 


I 


Relative humidity. 


Dew-point, 
7 p. m. 


Rainfall. 


Wind. 




7 a. m. 


7 p. m. 


I. m. 


7 p. m. 


Up- 
land. 


Marsh. 


7 a. m. 


7 p. m. 


Total. 


Pre- 
vail- 
ing 
direc- 
tion. 


Average ve- 
locity. 


Direction and ve- 
locity at time of 
minimum tem- 
perature. 




Up- 
land. 


Marsh. 


Up- 
land. 


Marsh. 


Up- 
land. 


Marsh. 


Upland. 


Marsh. 


1 


































2 


































3 


































4 


































5 































6. . .. 


















i 














7 


















1 














8 


































9 


































10 . .. 
































11 






























I 


12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 


29.78-F 

». 4e-s 

29.62-S 
29.56-S 

29.80-R 

29.82-S 
29.88-S 
30.00-R 
30. 30-R 

so.ss-s 

29.96-F 
30.08-S 
30. 12-S 
29.78-F 
29.60-S 
30.00-S 
30.06-F 
30.0O-S 
30.00-F 
30. 02-R 


i9.U-S 
29. 52-S 

29. 58-F 
29.70-R 

29.80-F 

29. 80-R 
29.88-R 
30.06-R 
SO.ilr-S 

30. 16-F 

29. 94-S 
30. 08-F 
30.00-F 
29.60-F 
29.80-F 
30. 06-S 
29. 94-S 
29.96-R 
29.98-S 
29. 94-F 


66 
52 

95 
97 

85 

90 
57 
49 
52 

76 

84 
89 
76 
83 
97 
60 
57 
56 
86 
68 


51 

94 
100 

92 

92 
59 
47 
48 

72 

91 
92 
78 
87 
100 
62 
55 
53 
88 
71 


37 

64 

96 
92 

79 

35 
32 
52 

47 

54 

83 
71 
58 
95 

100 
39 

.51 
53 
53 
40 


69 

100 
100 

96 

47 
46 
45 
60 

54 

91 
82 
59 
97 
100 
48 
50 
55 
53 
40 


33 

50 

45 
37 

50 

36 
28 
29 
29 

39 

47 
44 
40 
46 
35 
28 
43 
43 
46 
34 


58 

46 
39 

53 

41 
33 
24 
32 

38 

- 47 
46 
40 
47 
36 
32 
40 
43 
46 
34 


T. 
T. 

0.57 
.24 

.01 

.26 






1.65 





.03 

.02 

T. 







.10 


T. 


0.15 
.02 

.03 






T. 

.01 



T. 

.14 
■1.08 







T. 
T. 

0.72 
.26 

.04 

.26 




T. 

1.66 



T. 

.17 

a. 10 

T. 







.10 


S 
SW 

NW 
W 

SW 

NW 
NW 
NW 
NW 

SW 

NE 

E 

E 

NE 
NW 
NW 
SW 
SW 
SE 

E 


20.3 
16.3 

7.5 
9.8 

10.9 

8.0 
14.7 
14.5 

8.0 

7.2 

8.6 
10.7 
16.6 
14.4 
12.3 
16.4 
14.2 
7.3 
7.0 
11.5 


9.9 
7.3 

4.4 
6.3 

-5.7 

4.4 
8.6 
8.1 
4.0 

3.3 

4.5 
5.4 
8.6 
7.5 
7.7 
10.1 
6.5 
3.1 
3.4 
5.5 


SE 18 

SW 22 

NW 14 
W 10 

W 8 

N 7 
NW 7 
NW 6 
NW 5 

N 1 

SW 8 
N 8 
NE 12 
NE 16 
N 8 
NW 12 
SW 5 
SW 2 
NE 5 
NE 7 


8 
5 

3 

8 

3 

1 
2 
2 
2 

Calm. 

2 
5 
2 

Calm. 
Calm. 


Means 






74 


75 


63 


68 


39 


41 


62.88 


!i.43 


63.31 


NW 


11.8 


6.2 


NW 9 


3.1 









a Part snowfall. & Total. 

Marsh wet and water ia ditches high last half of month, due to frequent periods of cloudy and showery weather. Heavy rain on the22d together 
with flooding on tbe night of the 26th caused surface water to remain around Station 7 from the 22d to June 2, inclusive. 
Means for humidity and dew point for nineteen days. 

Highest and lowest readings are in italics. 



99 



Table 21. — Daily Weather Conditions, Mather, Wis., 1907. 

MAY. 



Temperature. 


Weather. 




Shelter Station 
1, Upland. 


Sta- 
tion 2, 
mini- 
mum.a 


Differ- 
ence — 
Mini- 
mum 
from 
mini- 
mum. 


Previous 
night. 


Day. 


Per 
cent 
of 
sun- 
shine. 


Miscellaneous. 


Maxi- 
mum. 


Mini- 
mum. 




81 


36 


35 


- 1 


Cloudv 


Partly cloudy. 


52 


Weather cleared after noon; distant lightning observed in evening. 


81 


Si 


SO 


- 4 


Clear 


do 


73 


Clear morning; partly cloudv afternoon; cloudy night with distant 














! lightning. 


48 


45 


45 





Cloudy 


Cloudy 





Showery, thunderstorm conditions. 


41 


36 


36 





do 


do 





Low, dense clouds continuous; light fog lilowing across marsh 7 to 
7.40 a. m. 


65 


35 


34 


- 1 


do 


Partly cloudy. 


36 


Cloudy until 10 a. m., partly cloudy to cloudy remainder of day; 
distant thunder and lightning in evening. 


71 


40 


32 


- 8 


Partly cloudy. 


do 


86 


Light fog early a. m. to 6.40 a. m. 






32 


16 


Clear. 




89 




53 


39 


28 


-11 


do 


Partly cloudy. 


87 


Partly cloudy during day with strato-cumulus clouds. 


56 


28 


18 


-10 


do 


Clear 


92 


Increasing cloudiness late in afternoon. Frost in morning, ice in imr- 




tionsof ditches, ground frozen in moist sections. Fog over ditches 
















and reservoir 7 to 8 p. m. 


65 


17 


21 


- 6 


do 


Partly cloudy. 


69 


Gradually increasing cloudiness during day, overcast after 2.30 p. m., 
heavy thunder hefore midnight. Ueary frost in morning. 


53 


45 


44 


- 1 


Cloudy 


Cloudy 


1 


Low clouds. Heavy thunderstorm in morning. 


57 


44 


44 





do 


do 


9 


Clearing after sunset. 


59 
49 


44 
45 


40 
44 


- 4 

- 1 


.do 


do 


11 



Alto-stratus clouds. 


do 


do 


Stratus clouds; light fog 6 p. ni. into the night. 


48 


43 


45 


+ S 


do 


do 





Frequent snow flurries with rain in evening. 




32 


27 


5 


Partly cloudy. 
Clear 


Clear 


85 


Thin ice observed this morning. No hoarfrost seen. 


69 
72 


34 
41 


27 
30 


- 7 
-11 


do 


100 

77 




do 


Partl.v cloudy. 


Light dew in morning. 


68 


45 


36 


- 9 


Partly cloudy. 


do 


45 


Do. 


68 


47 


45 


_ 2 


Cloudy 


do 


68 










61.3 


40.9 


36.2 


4.7 


49 















oin open over bog. 
Highest and lowest readings are in italics. 



100 

Table 21. — Daily Weather Conditions, Mather, Wis., 1907 — Continued. 

JUNE. 



Barometer— Rising 
(R), (ailing (F), sta- 
tionary (S). 



Relative humidity. 



Dew-point, 
7 p. m. 



Rainfall. 



Wind. 



1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

Means 



29.90-F 
29. 74-S 

29.70-R 
i9.S6-F 
29. 86-R 
30. 02-F 

29.88-S 
30. 04-S 

30.00-F 
29.62-F 
29. 64-R 
29. 82-R 
29. 98-R 
30. 10-R 
30. 12-F 
30. 12-F 
SO. H-S 
30. 10-S 
30.00-F 
29.90-F 
29. 94-F 
29. 90-S 
29. 90-S 
29. 94-F 

29. 86-R 

30. 00-S 
30.06-F 

29.92-F 
29.84-S 
29.80-F 



( p. m. 



29.76-F 
29. 72-S 

29.70-R 
29. 66-R 
29.94-R 

29. 94-F 

29. 92-S 
30. M-R 

29.84-F 
19. 48-R 
29.70-R 
29. 92-S 
-30.0O-R 

so.oe-F 

30.00-R 
SO. 06-S 
SO. 06-R 

SO. oe-R 

29 90-S 
29. 88-R 
29. 88-R 
29. 82-S 
29. 86-R 
29. 88-S 
29. 92-S 
30. 02-S 
29. 94-F 

29. 82-S 
29.76-S 
29.70-R 



Up- 
land. 



Marsh. 



I p. m. 



Up- 
land. 



Marsh. 



Up- 
land. 



Marsh 






T. 



0.05 








.06 















.08 







.22 

.07 



.68 














0.26 

T. 








.57 

.02 











T. 







.13 

T. 

T. 

T. 

T. 






T. 
.13 



Total, 



Pre- 
vail- 

direc- 
tion. 






0.26 
T. 

.05 

' 

! 






NE 
SW 

SW 
NW 
NW 

s 

SE 
E 



Average ve- 
locity. 



Up- 
land. 






SE 


.63 


E 


.02 


SW 





NE 





NE 





SE 





SW 





SW 


T. 


SW 


.08 


NW 





NW 





SW 


.13 


SE 


.22 


SW 


.07 


S 


T. 


S 


.68 


NW 





NW 





W 





SW 


T. 


SW 


.13 


SW 


a 2. 27 


SW 



9.9 
6.2 

7.4 
10.9 
15.8 



10.8 
9.7 

15. 5 
16.2 
9.3 
9.4 
9.3 
6.7 
8.0 
13.4 
10.6 
5.4 
5.4 
6.0 
8.2 
12.2 
7.1 
6.0 
10.6 
10.2 
5.9 

6.0 
7.4 
10.2 



Marsh. 



Direction and ve- 
locity at time of 
minimum tem- 
perature. 



Upland. 



4.3 
2.8 



8.9 
3.3 

4.8 
4.0 

7.1 
7.9 
3.9 
4.1 
4.1 
2.8 
3.2 
5.4 
4.9 
3.0 
2.7 
2.7 
4.0 
5.7 
3.3 
2.8 
5.8 
5.8 
2.8 

2.4 
2.9 
4.3 



NE 8 

NE 4 

S 7 

W 1 

NW 12 

SW 2 

SE 8 

N 7 



E 

E 

S 

N 

NE 
NE 
NE 
SW 
SW 
NW 
NW 
W 
SE 
SE 

S 

N 
NW 



3 
3 
10 
6 
3 
5 

NW 10 
NW 4 

NW 1 

S 4 
S 5 



Marsh. 



Calm. 

4 
Calm. 

8 
Calm. 

3 
Calm. 

Calm. 
10 

1 
Calm. 
Calm. 
Calm. 
Calm. 
Calm. 

2 
Calm. 

1 
Calm. 
Calm. 



Calm. 

Calm. 

7 

Calm. 

Calm. 
Calm. 
Calm. 



54 



9.2 



NW 6.1 



1.4 



n Total. 
Marsh continued wet fore part of month, and flooding occurred on the nights of the 5th and 13th. Decidedly warmer weather set in 
Immediately after the 13th, and by the end of the month the marsh was considerably drier and the water in the ditches about normal. 

Highest and lowest readings are in italics. 



101 



Table 21. — Daily Weatheb Conditions. Mather, Wis., 1907 — Continued. 

JUNE. 



Temperature. 



Shelter Station 
1, Upland. 



Maxi- 
mum. 



Mini- 
mum. 



36 
39. 

55 
41 
44 

Si 

48 
36 

41 
54 
47 
53 
44 
39 
43 
54 
70 
59 
57 
51, 
49 
61 
60 
54 
58 
48 
45 

43 
51 
58 



Sta- 
tion 2, 
mini- 
mum. o 



Differ- 
ence— 
Mini- 
mum 
from 
mini- 
mum. 



42.3 



- 2 



Previous 
niglit. 



Dav. 



Clear... 
do. 



Cloudy 

do 

Partly cloudy. 
Clear 



Cloudy. 
Clear... 



Partly cloudy. 

Cloudy 

do 

Partly cloudy. 

Clear 

do 

do 

do 

Partly cloudy. 

do 

Clear 

do 

Partly cloudy. 

Cloudy 

Partly cloudy. 

do 

Cloudy 

Clear 

do 



do 

Partly cloudy 
Clear 



Clear 

Partly cloudy. 



Cloudy 

Partly cloudy. 

Clear 

Partly cloudy. 



.do. 
.do. 



Cloudy 

do 

do 

do 

Clear 

do 

Partly cloudy, 

do 

do 

do 

Clear 

do 

Partly cloudy. 

do 

Cloudy 

Partly cloudy. 

do 

Clear 

do 



do 

Partly cloudy. 
....do 



Per 

cent 
of 
sun- 
shine. 



100 

80 

13 
51 
100 

73 

42 
90 

31 
8 
10 
33 
100 
100 
94 
92 
79 
63 
100 
99 
73 
50 
54 
80 
72 
100 
100 



Miscellaneous. 



Light frost in morning. 

Heavy dew in morning; fog over marsh Ijefore sunrise. Distant light- 
ning in evening. 
Partly cloudy in evening. 
Dense fog in early morning; heavy gale after 3 p. m. 

Light frost in morning. Moss and moist ground frozen; strawberry 
leaves on uplands frosted. Heavy dew observed in spots. 

Clearing after 9 p. m. 

Frost in morning. Moss frozen hard in places. Some instruments, 
especially thermographs, heavily coated with frost. 

Distant thunder in early morning. 



Hea\'y dew l>egan to form liefore sundown. 
Heavy fog over marsh in evening. 
Heavy dew in morning; frost obscrird in patches. 
Heavy dew in morning. 



Thimderstorm conditions. 

Heavy dew and dense fog over marsh in early morning. 
Thunderstorm conditions. 



Thtinderstorm conditions. Heavy dew and dense fog in morning. 

Heavy dew and dense fog over marsh in evening. 

Heavy dew and dense fog over marsh in early morning and again at 

night. 
Heavy dew and dense fog over marsh in early morning. 
Thunderstorm conditions. 
Do. 



a In open over bog. 
Highest and lowest readings are in italics. 



102 

Table 21. — Daily Weather Conditions, Mather, Wis., 1907 — Continued. 

jCly. 



Barometer— Rising 
(R), falling (F), .sta- 
tionary (S). 



Relative humidity. 



Dew-point, 
7 p. m. 



Rainfall. 



7. 
8. 
9; 

10. 



29.86-R 
30. 10-r 
30.10-F 

30. 00-S 

29.82-S 
29.93-R 
29.90-F 
29.92-S 
29.96-S 
29.92-F 



11 29.84-R 



12. 
13. 
14. 
13. 
16. 
17. 
18. 
19. 
20. 
21. 
22. 
23. 
24. 
25. 
26. 
27. 
28. 
29. 
30. 
31. 



Means 



30.04-S 
29.94-F 
29.74-S 
29.BJ,-F 
29.92-S 
30. 06-S 
SO. 12-S 
29.94-F 
29. 98-S 
29.90-F 
29. 86-R 
29. 98-r 
29. 80-S 
29.78-F 
29. 98-S 
30. 04-F 
29.84-F 
29.92-S 
29.98-F 
29.92-S 



7 p. ni. 



29. 98-R 
30. 06-S 
29.90-S 

29.94-F 

29.84-R 
29.90-R 
29.82-R 
29. 92-R 
29. 90-S 
29. 82-S 

29. 92-R 

30.00-F 
29. 80-S 
29. 72-S 
29. 74-R 

29. 88-S 
SO. lO-S 

30. 00-F 
29. 90-R 
29. 96-R 
29. 70-S 
29. 96-R 
29. 84- F 
29. 80-S 

29. ee-R 

30. 02-S 
29. 90-F 
29. 76-R 
29.94-R 
29. 92-S 
29.86-F 



Up- 
land. 



81 
72 
95 
100 
98 
S3 
98 
96 
S3 
98 
93 
80 
76 
94 
75 
85 
74 
81 
74 



p. m. 



Up- 
land. 



iS5. M^^h- 



90 



92 
81 
86 
91 
95 
100 
91 
93 
91 
92 
93 
76 
66 
75 
89 
95 



85 



62 



Marsh. 



T. 



0.35 



2.15 






.03 





.18 

.52 







.09 



.89 

.02 











T. 









7 p. m. 



T. 



0.35 

.03 

.01 





.05 







.02 

.13 

.02 



.03 





3.89 



T. 



.02 









.20 





Total. 



Pre- 
vail- 
ing 
direc- 
tion. 



T. 


0.70 

.03 

2.16 




.05 

.03 




.20 
.65 
.02 


.03 
.09 



4.78 

.02 

T. 


.02 




T. 


.20 





NW 

NE' 
SW 
SW 

SE 

N 
NW 
SW 
NW 
NW 
NE 
NE 
NW 
SE 
SW 
SW 
NW 
SW 
NW 
SE 

W 
NW 

S 
NW 
SW 
NW 
SW 
NW 
SW 

W 
NW 
NW 
NW 



NW 



Average ve- 
locity. 



Up- 
land. 



11.6 
4.5 



7.3 
5.5 
5.9 
6.8 
5.6 
4.5 

6.0 

4.8 
11.4 
10.1 
10.4 
7.5 
8.9 
5.6 
8.2 
5.2 
7.2 
9.0 
6.3 
7.5 
8.8 
8.3 
5.4 
9.6 
9.4 
8.6 
9.2 



Marsh. 



7.0 
1.8 
3.7 



4.0 
2.8 
2.7 
3.5 
2.9 
2.0 

3.4 

1.9 
4.8 
5.1 
5.8 
3.6 
5.0 
2.3 
4.5 
2.6 
3.5 
5.2 
2.8 
4.0 
4.9 
4.8 
2.5 
5.2 
5.0 
4.5 
4.8 



Direction and ve- 
locity at time of 
minimnm tem- 
perature. 



Upland. 



NW 8 

N 5 

SW 3 

SE 2 



SE 
NW 

W 
NW 

NW 

N 



NE 3 



N 


4 


Calm. 


S 


4 


Calm. 


S 


8 


2 


SE 


12 


7 


N 


4 


Calm. 


NW 


5 


1 


NW 


4 


Calm. 


SE 


4 


Calm. 


W 


6 


2 


s 


4 


Calm. 


NW 


5 


3 


N 


3 


Calm. 


SW 


5 


2 


N 


2 


Calm. 


N 


8 


4 


W 


2 


Calm. 


SW 


5 


Calm. 


NW 


9 


3 


NW 


4 


Calm. 


NW 


8 


3 



Marsh. 



Calm. 
Calm. 

Calm. 



Cain 



Calm. 



NW 5.0 1.2 



o Total. 
With the exception of a heavy rain on Ihe 5th which kept the water in the ditches high for several days, the condition of the marsh during 
the first half of the month was nearly normal. A period of showery weather set in on the 14th, culminating in an unusually heavy rain on the 21st, 
which completely flooded the marsh and raised the water in the reservoir 4 inches above high-water mark. This was further augmented by the 
breaking down of a dam on the marsh above. Station 7 was covered with water to adepth of nearly 12 inches for three days after the 21st, and the 
water did not entirely disappear until the 1st of August. 

Highest and lowest readings are in italics. 



103 



Table 21. — Daily Weather Conditions, Mather, Wis., 1007 — ('oniinued. 

JULY. 



Temperature. 



Shelter Station 
1, Upland. 



Maxi- 
mum. 



79.7 



Mini- 
mum. 



Sta- 
tion 2, 
inini- 
mum.a 



Differ- 
ence — 
Mini- 
mum 
from 
mini- 
mum. 



49.0 



Previous 
night. 



Cloudy 

Clear 

Partly cloudy. 



Clear. 



Partly cloudy. 

Cloudy, 

Clear 

do 

Cloudy 

Partly cloudy. 



Day. 



Partly cloudy. 

Clear 

Partly cloudy. 

do 



do 

do 

Clear 

Partly cloudy. 

Cloudy 

do 



Cloudy ! Partly cloudy. 



Partly cloudy. 

do 

Cloudy 

do 

Partly cloudy. 

Clear 

Partly cloudy. 

Cloudy 

Clear 

Cloudy 

Partly cloudy. 

Clear 

do 

Partly cloudy. 

do 

....do 

Cloudy 

Clear 

....do 

...do 



do 

do 

Cloudy 

do 

do 

Clear 

Cloudy 

Partly cloudy. 

do 

Cloudy 

Partly cloudy. 

do 

Clear 

Partly cloudy. 

Clear 

Cloudy 

Partly cloudy. 

Clear 

Partly cloudy. 
Clear 



Per 
cent 
of 
sun- 
shine. 



72 
100 
59 



91 
71 
40 
47 
38 

100 
29 
66 
84 

75 
79 

100 
56 

100 
57 
82 
97 
80 
94 

68 



Miscellaneous. 



Heavy dew in evening. 

(Heavy dew in morning. No frost observed, but light fnisi probably 
I occurred in portions of marsh Ijefore daybreak. 

Dense fog in early morning and previous night. Severe thunder- 
storm conditions in vicinity. 

Severe thunderstorm in evening with liail and heavy rain, flooding 
marsh and injuring cranberries. 

Thunderstorm conditions in morning. 

Dense fog in early morning, clearing about 2 p. m. 

Distant thunderstorm in evening. 



Clearing toward night. 
Distant lightning in evening. 



Thunderstorm in early morning. 

Heavy thunderstorm flooding marsh and reservoir. 

Distant thunderstorm in evening. 



Thunderstorm in afternoon. 
Cloudy in evening. 



o In open over bog. 
Highest and lowest readings are in italics. 



104 

Table 21. — Daily Weather Conditions, Mather, Wis., 1907 — Continued. 

AUGUST. 



Barometer — Rising 

(R), falling (F), sta- 

tionar.v (S). 



Relative huniiditv. 



Dew-point, 
7 p. m. 



Rainfall. 



1. 
2. 
3. 

4. 
5. 
6. 

7. 

8. 

9. 
10. 
11. 
12., 
13. 
14., 
15., 
16.. 
17.. 
18.. 
19.. 
20.. 

21.. 

22.. 
23.. 
24.. 
25.. 
26.. 
27.. 
28.. 
29.. 
30.. 
31.. 



29. 72-F 
29.88-R 
30. 04-R 
30.06-F 

29. 74-R 
30.02-F 

30. 04-R 
30. 16-F 
3a08-F 
30.00-F 
«9. 70-S 
30. 02-R 
30 18-R 

SO. ess 

30.0D-F 
29. 80-R 
30. 04-S 
30. 16-F 
29.90-S 

SO. ess 

30. 24-S 
30 20-F 
29.90-F 
29.90-R 
30. 04-F 

29. 94-S 
29. 80-R 

30. 04-R 
29. 98-S 
29. 98-R 
30. 14-F 



7 p. m. 



Up- 
land. 



S9. 71-S 
29. 94-R 
30. 04-S 
29. 86-F 

29. 88-R 
29.90-R 

30. 06-S 
30. 08-S 
30. 00-S 
29. 84-F 
29. 76-R 
30. 00-S 
30. 20-R 
30. 10-S 

29. 80- F 
29. 88-R 
30. 06-R 
29. 96-F 
30.00-R 

30. SS-S 

30 14-F 
30. 00- F 
S9. 71-E 
29. 92-R 
29. 96-F 

29. 76-F 
29. 92-R 

30. 00-S 
29. 90-S 
30. 00-R 
30. 08-S 



Means 



97 
90 
88 
90 
97 
82 
79 
90 
73 
62 
88 
66 
82 
76 
80 
88 
64 
85 
76 
69 

73 
85 
78 
64 
74 
91 
97 
69 
69 
92 



Marsh. 



r p. m. 



Up 
land. 



Up- 
land. 



Marsh, 



91 
80 
90 
72 
91 
92 
90 
91 
89 
72 
71 
77 
73 
92 
88 
48 
86 
82 
69 
95 

79 
63 
84 
70 
87 
99 
89 
85 
93 
86 
80 



82 



Marsh. 



51 

.01 



.10 

T. 





T. 


.06 



T. 

1.35 


2.28 






.37 



T. 



.24 

.05 



a 4. 97 



7 p. m. 



0.09 

T. 







.05 



T. 





.54 



T. 




.34 





T. 


.78 



T. 

T. 

T. 



Total. 



Pre- 
vail- 
ing 
direc- 
tion. 



0.60 

.01 





.10 

.05 



T. 

T. 



.60 





T. 

T. 

1.35 





2.62 







T. 

.37 



.78 

T. 



T. 

.24 

.05 



NW 
NW 

NW 

sw 
w 
sw 

NW 
SE 
S 

s 
sw 

NW 
NW 
SE 
S 
SW 
NW 
SW 
SE 
NW 

SW 
SW 
SW 

sw 

NW 
SE 

sw 
w 

SE 
NW 
SE 



6 6.77 



SW 
NW 



Average ve- 
locity. 



Up- 
land. 



12.8 
9.9 
6.3 
9.9 
11.9 
12.8 
6.0 
8.3 
6.2 
11.5 
12.6 
9.4 
4.8 
7.9 
10.8 
15.0 
5.3 
15.9 
12.2 
7.5 

3.8 
8.5 
12.8 
13.5 
6.8 
7.5 
4.4 
2.5 
5.5 
3.2 
7.3 



7.4 
5.9 
3.4 
4.8 
6.5 
5.2 
3.3 
4.1 
2.9 
5.8 
6.6 
4.6 
2.2 
3.5 
5.3 
8.5 
2.2 
8.6 
6.6 
4.0 

1.7 
3.5 
5.7 
7.4 
3.6 
3.6 
2.4 
1.0 
2.5 
1.4 
3.3 



Direction and ve- 
locity at time of 
minimum tem- 
perature. 



Upland. Marsh. 



NW 5 

NW 10 

NW 8 

S 3 

SW 11 

S 5 

NW 10 

S 3 

SE 5 

S 6 

SW 7 

NW 8 

NW 11 

NE 4 

S 10 

SW 5 

NW 6 

SW 6 

SE 6 

NW 12 

SW 2 

SW 3 

SW 5 

SW 10 

NW 5 

E 10 
SW 
NE 
SE 

N 

E 



SW 

NW 



Calm. 



Calm. 
7 

Calm. 
4 
1 

Calm. 

Calm. 
5 

Calm. 
5 

Calm. 
2 
2 
1 

Calm. 
2 
1 

Calm. 

Calm. 
1 
3 
2 
1 
2 

Calm. 

Calm. 
1 

Calm. 



tt Total. 

Marsh continueii wet and water in the ditches4iigh all of the month. 

Highest and lowest readings are in italics. 



105 

Table 21.— Daily Weather Conditions, Mather, Wis., 1907— Continued. 

AUGUST. 



Temperature. 



Shelter Station 
1, Upland. 



Maxi- 
mum. 



68 
68 
74 
79 
84 
80 
76 
85 
89 
80 
79 
81 
85 
82 
79 
85 
84 
74 
66 

74 
74 
78 
72 
73 
84 
69 
76 
68 
75 
89 



Mini- 
mum. 



76.7 



Sta- 
tion 2, 
mini- 
mum.a 



55 
46 
48 
39 
59 
54 
57 
55 
54 
59 
74 
53 
50 
53 
56 
61 
52 
57 
65 
43 

47 
43 
54 
54 
^8 
51 
56 
58 
51 
64 
58 



Differ- 
ence — 
Mini- 
mum 
from 
mini- 
mum. 



47 
39 
40 
34 
58 
46 
43 
51 
49 
55 
70 
40 
42 
46 
50 
58 
43 
48 
65 
34 

36 

34 
47 
41 
SS 
42 
56 
50 
44 
62 
52 



Weather. 



Previous 
night. 



Day. 



Partly cloudy. 

Cloudy 

Clear 

Cloudy 

do : 

Partly cloudy. 

Clear 

Partly cloudy. 

Cloudy 

Partly cloudy 

Cloudy 

Clear 

do 

Partly cloudy. 

Clear 

Partly cloudy 

Clear 

do 

Cloudy 

Clear 



Partly cloudy. 

Clear 

Partly cloudy. 

do 

Clear 

Partly cloudy. 

Cloudy 

Clear 

Partly cloudy 

Cloudy 

do 



Per 
cent 
ot 
sun- 
shine. 



Miscellaneous. 



Partly cloudy, 

do 

do 

do 

Clear 

Partly cloudy. 

Clear 

Cloudy 

Clear 

do 

Partly cloudy. 

Clear 

do 

do 

Partly cloudy 

Clear 

do 

do 

Partly cloudy 
Clear 



....do 

....do 

Partly cloudy. 

do 

Clear 

Cloudy 

Partly cloudy 

Clear 

Cloudy 

Partly cloudy 
Clear 



49 
55 
90 
69 
90 
47 
94 
18 
90 
83 
48 
100 
95 
80 
84 
100 
100 
100 
49 
100 

91 
91 
92 
92 
95 
10 
36 
100 
4 
50 
85 



Thunderstorm in early morning. 
Dense fog over marsh in evening. 



Thunderstorm conditions. 



Cloudy late in the evening. 
Heavv thunderstorm in morning. 



Moderately heavy dew in morning. 
Thunderstorm in evening. Light dew in morning. 



Moderately heavy dew in morning. 
Thunderstorm conditions. 

Dew ijegan before sunset; fog over marsli in evening. Cloudy at mid- 
night. 
Fog appeared over marsh at sunset. 
Heavy ground fog over marsh at 5 a. m. 
Thunderstorm. 



a In open over bog. 
Highest and lowest readings are in italics. 



106 

Table 21. — Daily Weather Conditions, Mather, Wis.. 1907 — Continued. 

SEPTEMBER. 



1., 

2.. 
3., 
4.. 
5.. 
6.. 

7., 
8.. 
9.. 

10.. 

11. 

12. 

13. 

14. 

15. 

16., 

17. 

18. 

19. 

20. 

21. 

22. 

23. 

24. 
25. 
26. 
27. 
28. 
29. 
30. 



Barometer — Rising 
(R), falling (F), 
stationary (S). 



Means.' 



7 a. m. 



30. 02-S 
29.90-F 
29.80-S 
29.90-S 
30. 08-S 
30. 08- F 

29. 78-r 
29.82-S 
30. 02-R 
30. 04-S 
29.94-R 
30. 12-R 
30. 14-R 
30.00-S 
30. 08-E 
30.00-S 
30. 04-S 
30. 04-F 
29. 92-F 
29. 78-R 
30.0O-S 
30.08-F 

S9.i8-F 
29.58-R 
30.26-R 
30. 20-S 
30.00-S 
29.88-S 
30. 02-S 
SO. ss-s 



Relative humidity. 



Up- 
land. 



29.90-R 

29.86-S 
29. 84-S 
29. 92-R 
30.06-S 
29.94-F 

29. 8b-R 
29. 92-R 
30. 08-R 
29.96-F 
29.98-R 
30. 12-S 
30. 00-S 
30.00-R 
30. 10-F 
30. 04-R 
29.98-F 
29. 92-F 
29. 72-F 
29.98-R 
30. 06-S 
29. 76- F 

29. S6-R 
30. 02-R 
30.26-F 
30.08-F 
29.90-S 
29.96-S 
30. 06-R 
30.S0-F 



Marsh. 



S. M^^h. 



91 
92 
80 
76 
76 
68 
96 
97 
97 
95 
94 
81 
77 

95 
81 
87 
83 
94 
74 
72 



74 



Dewpoiut, 
7 p. m. 



Up- 
land. 



85 



Marsh. 



52 



55 



T. 

0.01 




.31 

.27 















.14 

.01 

.25 

.40 

.41 





.10 










7 p. m. 



O1.90 







0.01 

.03 


.04 

T. 



.01 


T. 





.75 

T. 




T. 

.14 
T. 





.02 




ol.OO 



Total. 



T. 



0.02 

.03 



.04 

.31 

.27 



.01 



T. 







.14 

.76 

.25 

.40 

.41 



T, 

.24 
T. 





.02 




2.90 



Pre- 
vail- 
ing, 
direc- 
tion. 



NW 
NW 
NW 
NW 
NW 
W 

E 
NW 
NW 
NW 
NW 

sw 

SE 

sw 

SW 
SW 
NE 
SW 
NE 
W 
SW 
SW 

W 
NW 

w 

SW 
NE 
NE 

NW 
S 



NW 



-Average ve- 
locity. 



Up- 
land. 



11.1 
11.0 
8.0 
9.1 
7.8 
4.0 

5.6 
9.5 
9.3 
3.2 
10.8 
7.4 
14.4 
14.5 
10.4 
10.1 
11.5 
10.2 
14.0 
14.6 
13.1 
18.8 

13.3 
19.5 
8.1 
8.2 
10.2 
7.9 
7.5 
5.1 



Marsh. 



9.9 



6.2 
6.2 
4.5 
5.3 
4.0 
l.S 



5.2 
5.1 
1.1 
5.6 
816 
7.2 
5.9 
4.5 
5.0 
5.8 
4.7 
6.8 
8.2 
6.9 
4.0 

7.3 
11.4 
4.3 
3.1 
4.8 
3.6 
4.1 
2.0 



5.0 



Direction and ve- 
locity at time of 
minimum tem- 
perature. 



Upland. 



NW 8 

NW 9 

NW 6 

NW 10 

NW 12 

SW 2 



E 
NW 
NW 

N 
NW 

W 
SW 

sw 
w 

sw 13 

SW 5 

S 4 

NE 6 

NW 17 

SW 4 

SW 4 

W 10 

NW 30 

W 6 

SW 4 

NE 3 

NE 9 

S 1 

W 3 



Marsh. 



Calm. 



3 

Calm. 

1 

Calm. 

Calm. 

4 

1 

4 

2 

2 

3 

13 

1 

1. 

1 
10 

3 

1 
Calm. 

5 
Calm. 



NW 7. 7 



2.8 



a Total. 
Marsh continued wet and water in ditches high all of I he month, flooding in anticipation of frost l^.'ing frequent during latter part of the month. 

Highest and lowest readings are in italics. 



107 



Table 21. — Daily Weather Conditions, Mather, Wis.. 1907 — Continued. 

SEPTEMBER. 



Temperature. 



Shelter Station 
1, Upland. 



Maxi- 
mum. 



68 
65 

06 
71 

67 

64 
65 
68 
64 

73 
78 
80 
82 
Si 
81 
74 
79 
Si 
66 
62 
64 

62 
i9 
55 
63 
55 
60 
60 
61 

68.3 



Mini- 
mum. 



TO 
53 
50 
52 
44 
41 

54 
56 
40 
38 
45 
48 
50 
62 
63 
67 
53 
58 
61 
60 
38 
31 

45 
43 

es 

34 
34 
37 
29 
2S 



.Sta- 
tion 2, 
miui- 
inum.a 



Difler- 
ence — 
mini- 
mum 
from 
mini- 
mum. 



61 
42 
40 
45 
36 
33 

55 
56 
30 
30 
37 
37 
40 
57 
54 
6i 
44 
56 
58 
57 
30 
23 

37 
40 
20 
25 
27 
35 
25 
19 



40.4 



- 9 
-11 
-10 

- 7 

- S 

- 8 

+ 1 



-10 

- 8 

- 8 
-// 
-10 

- 5 

- 9 

- 3 

- 9 
_ 2 

- 3 

- 3 



Previous 
night. 



Partly cloudy. 

....do 

....do 

Cloudy 

riear 

Partly cloudy 



Clear 

do 

Partly cloudy 
do 

Clear 

Cloudy 



I 



Cloudy 

....do 

Clear 

Partly cloudy. 

. ...do 

Clear 

Partly cloudy. 

Clear 

do 

Cloudy 

Partly cloudy 

Cloudy 

do 

do 

Partly cloudy 
Clear 



Cloudy 

do 

Clear 

Partly cloudy 



....do 

Partly cloudy. 

Clear 

Cloudy 

Partly cloudy 

Clear 

do 

do 

Partly cloudy. 

Clear 

Cloudy 

Partly cloudy, 

do 

Clear 

Partly cloudy 
do 



Per 
cent 
of 
sun- 
shine. 



Miscellaneous. 



Cloudy 

do 

Clear 

Partly cloudy 



Cloudy Cloudy 

do I Partly cloudy 

Partly doudy. Cloudy 

Clear Partly cloudy 



94 
100 
41 
60 



1 
50 

100 
24 
60 
72 

100 
93 
88 
85 
31 
46 
63 
72 
70 
70 

18 
21 
100 
38 


33 

86 



Cloudy in evening. 



Fog began to form about 8 p. m. 

Fog quite dense in morning, especially over marshes; grass very wet 
from dew and fog. 



Dew began to form at 6 p. m.; light fog over marsh in evening. 
Although minimum temperature was low, no frost was observed. 

Increasing cloudiness in afternoon. 



Thunderstorm in morning. 

Do. 
Thunderstorm conditions. 
Thunderstorm in early morning. 



■ I 



Killing frost in morning; frost first oliserved last night at 10.30 on 
marsh. 

Clearing at night. 
Killing frost. 

Do. 
Ligtit frost. 

Ground fog on marsh after 5.45 p. m. 
Killing frost . 
Killing frost , ifry lifaiy deposit. 



a In open over bog. 
Highest and lowest readings are in italics. 



108 

Table 21. — Daily Weather Conditions, Mather, Wis., 1907 — Continued. 

OCTOBER. 



Barometer — Rising 
(Rj, falling (F), 
stationary (S). 



Relative humidity. 



Dewpoint, 

7 p. ni. 



Rainfall. 



Wind. 



( p. m. 



Up- 
land. 



Up- 
land. 



Up- 
land. 



Marsh, 



Marsh. 



7 p. m. 



Total. 



Pre- 
vail- 
ing 
direc- 
tion. 



Average ve- 
locity. 



Up- 
land. 



Marsh. 



Direction and ve- 
locity at time of 
minimum tem- 
perature. 



Upland. Marsh. 



1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 
10. 
U. 
12. 
13. 
14. 
15. 
16. 
17. 
18. 
19. 
20. 
21. 
22. 
23. 
24. 
25. 
26. 
27. 
28. 
29. 
30. 
31. 



30. is-r 

29.86-R 
29.86-S 
29. 96-S 
29.98-R 
29.80-F 
S9. 60-R 
30.22-S 
29.90-S 
29.84-F 
30.0O-E 
30.28-S 
SO. U-R 
30.28-F 
30. I2-S 
30. 16-S 
30. 08-F 
30.42-S 
30.28-F 
30.20-R I 
30.42-F j 
29.90-F 
30. 14-S 
30. ll-F 
30. 22-R 
30. 22-F 
29.94-R 
30. 30-F 
30. 16-S 
30. 26-R 
30. 26-F 



29.86-F 
29.90-S 
29.80-R 
29.88-S 
30.0O-F 
B9.e0-F 
29.94-R 
30. 10-F 
29.98-S 
29.86-S 
30. 14-R 
30. 32-S 
30.32-F 
30. 12-S 
30. 14-S 
30. 12-S 
30. 10-R 
S0.40-F 
30.04-F 
30. 36-S 
30. 10-F 
29.94-R 
30. 18-S 
29.98-R 
30. 32-S 
29.90-F 
30. 26-R 
30. 18-S 
30.22-S 
30. 30-F 
30. 14-F 



85 



60 
86 
75 
60 
86 
84 
53 
63 
82 
44 
87 
82 
85 
87 
87 
76 
77 
81 
64 
61 
84 
88 
97 
56 




0.04 

.09 

.01 



.02 




.03 




.10 








T. 




T, 



T. 

.10 



0.08 

.01 



.06 


T. 


T. 



T. 





T. 




T. 



T. 

T. 


T. 

.05 





0.08 

.04 

.10 

.01 



.08 


T. 


.03 



T. 

.10 




T. 




T. 



T. 

T. 


T. 

.05 

.10 



SE 

sw 
sw 
w 

NW 
SW 
NW 
SW 
NW 
NW 
NW 
NW 
NW 
SW 
SW 
SW 
SW 
NW 
SW 

N 
SW 

W 
SW 
SW 

N 

SW 
NW 
SW 

E 
SE 
SE 



13.0 

5.7 

7.6 

8.6 

7.9 

14.4 

11.4 

8.7 

15.9 

16.2 

14.0 

10.2 

5.6 

7.8 

8.0 

5.4 

13.7 

8.8 

5.6 

6.9 

10.6 

11.7 

5.4 

11.5 

7.7 

8.0 

14.7 

6.1 

8.7 

9.5 



6.5 
2.2 
4.0 
4.4 
3.7 
6.5 
6.5 
3.8 
8.1 
8.9 
8.4 
6.1 
2.5 
3.2 
3.8 
1.9 
6.9 
4.8 
2.6 
3.7 
4.0 
5.7 
2.1 
5.7 
3.9 
3.4 
8.7 
2.4 
4.1 
4.6 



SE 5 

SW 6 

NE 7 

W 5 

NW 6 

NW 6 

NW 12 

SW 4 

NW 9 

NW 3 

NW 10 

NW 12 

NW 4 

SW 

SE 
SW 
NW 
NW 
NW 

NE 9 

SW 3 

NW 8 

SE 6 

S 6 

NW 8 

NW 6 

NW 17 

SW 4 

NE 5 

SE 7 

E 6 



2 
1 

Calm. 
2 
2 
1 
2 
1 
4 
1 
7 
7 
3 

Calm. 
4 

Calm. 

Calm. 
7 
1 
4 
1 
4 
1 
3 
3 

1 

2 

Calm. 

2 

3 

2 



Means. 



81 



66 



38 



11.20 a. 59 



SW 



4.8 



NW 6.6 



2.3 



a Total. 

Marsh was much drier this month than at any time previous this season, except in the latter part of June, although water in the ditches remained 
high until about the 10th of the month. 

Highest and lowest readings are in italics. 



109 



Table 21. — Daily Weather Conditions, Mather. Wis., 1907 — Continued. 

OCTOBER. 



Temperature. 



Shelter Station 
1, Upland. 



Maxi- 
mum. 



Mini- 
mum. 



Sta- 
tion 2, 
mini- 
mum a. 



25.3 



Differ- 
ence — 
mini- 
mum 
from 
mini- 
mum. 



- 7 
-10 

-U 
-U 

-10 
-13 

- 7 

- 7 
-10 

- 9 

- 6 

- 9 

- 6 

- 5 

- 7 
-12 

- 6 

- 9 

- 6 

- 6 

- 9 

- 8 
-U 
-11 

- 7 



Previous 
night. 



Partly cloudy. 

Cloudy 

Partly cloudy. 

do 

Clear 

Partly cloudy, 

do 

Clear 

Cloudy 

Partly cloudy. 

do 

Cloudy 

Clear 

do 

Cloudy 

Partly cloudy. 

Clear 

do 



Day. 



Cloudy 

Partly cloudy. 

Cloudy 

Partly cloudy. 

Clear 

do 

Cloudy 

Partly cloudy. 

Cloudy 

Clear 

Cloudy 

do 

Clear 

Partly cloudy. 

do 

do 

Clear 

do 



Partly cloudy. Cloudy.. 
do Clear 

Clear [ do.. 

Partly cloudy. [ do. . 

do do.. 



....do 

....do 

Partly cloudy. 



do 

Clear 

Partly cloudy. 

Cloudy I Cloudy 

Partly cloudy. Clear,. 

Clear Cloudy 

Cloudy do. 

do i do. 



Per 

cent 
of 
sun- 
shine. 



21 

65 
IS 

70 
83 
85 


75 


72 
11 
13 
100 
70 



100 


100 

100 
83 
98 
86 

100 

69 



100 
34 
10 
44 

38 



Miscellaneous. 



No frost or dew observed. 



Lightfrost. 
Do. 



Heavy and killing frost; looked like light, snow; thin ice formed. 

No frost ol)Serve(l. 

Heavy and kilting frost; ice formed. 
Killing frost and ice; aurora in evening. 
Killing and heavy frost and ice. 

Dense fog from last midnight until 11 a. m. 

Light fog in evening over marsh. 

Killing frost, light in amount, but damp ground froze. 

First snow flurry of the season; severe freeze. 

Freezing. 

Very heavy deposit of frost. Ice on reservoir. 

Frost. 

Freezing. 

Frost. 

Heavy frost in morning. 

Snow in morning. 

Exceedingly heavy frost deposit. 



a In open over bog. 
Highest and lowest readings are in italics. 



110 

Comparison between temperatures in the bog at Mather, Wis., and at United States Weather Bureau 
Office, La Crosse, Wis. — While numerous references liave been made to the mininiuni tAiiperature 
readings at La Crosse, a more complete comparison between the temperature at that place and 
Mather should be of interest, especially to those who are well acquainted with the daily weather 
map. Forecasters must look to the forecast chart for their general information, and many of 
them are accustomed to consider reports from certain stations as " keys" to conditions prevailing 
in adjacent sections. La Crosse may be considered as a "key" to the cranberry mareh region 
of Wisconsin. It is situated about55 miles southwestof Mather, and is an old established station 
of the Weather Bureau. The thermometers at La Crosse were at the time of this investigation 
located in an instrument shelter on the roof of the federal building. Thus far the study has 
been confined mainly to the temperature conditions in the bogs, showing the witle range in 
even the same bog; and references have been made to the general weather conditions prevail- 
ing as shown by the daily weather maps. Some mention has also been made of the tem- 
])erature readings at La Crosse in connection with the marsh readings in Wisconsin, and now 
a comparison of observations of temperature at both La Crosse and Mather for the entire season 
of 1907, Tables 22 and 22a should prove interesting. The maximum temperature readings are 
not included in the table, as a comparison of them does not seem to be important. 

The minimum shelter readings at Station 1 at Mather averaged 5.2° lower than at La Crosse 
(Table 22a), and the average diflference was greatest in June, 7.1°, and least in September, 3.6°. 
The temperature in the shelter over the mosd at Station 2 on the bog averaged 8.7° lower than 
at La Crosse, and the greatest monthly difference was again in June, 10.8°, and the least in 
September, 6.4°. The minimum exposed over the moss at the height of 5 inches on the bog 
averaged 11.9° lower than at La Crosse, and the greatest jnonthly difference was in June, 13.9°, 
and the least in May, 8.5°. The minimum in the open on the bog at Mather averaged 3.2° 
lower than that in the shelter nearby. The greatest difference on any one day in the various 
months between the temperature at La Crosse antl that in the open over the moss at Mather was 
20° in May, 24° in June, 21° in July, 19° in August, 20° in September, and 22° in October. 
Often there were days of very little difference when the weather was cloudy, and there were a 
few instances where the temperature in the bog at Mather was even higher than at La Crosse. 
This is not surprising in view of the fact that these stations are 55 miles apart, and that occasion- 
ally the weather conditions at the two places differ considerably. What we should consider in 
the study of these readings is the average difference under all conditions, the average difference 
when the pressure is high and the weather clear, and the extreme differences. While extreme 
differences of 22 to 24 degrees maj- occur, there are usualty days in every month when the tem- 
peratui-e in the bog is 20° lower than at La Crosse. The average difference when the weather 
is clear and the pressure high is about 18°, so that when the temperature at La Crosse is 50° 
during the conditions favorable for frost, it is probable that the temperature at the coldest places 
on the bog is as low as 32°. The latter has reference, however, to the reading of a minimum 
thermometer in the open, and ordinarily, the reading of the exposed minimum at the coldest 
point in the bog must be below 30° to cause any damage. On August 8, 1904, when the mini- 
mum temperature at La Crosse was 48°, the memorable midsununer freeze occurred which 
destroyed the greater portion of the Wisconsin crop, minimum temperatures in the bogs 
being as low as 26°. Frost usually formed on the thermograph before it did on the vegetation, 
indicating that the black metal cover of the instrument loses heat even uiore rapidly than the 
vines and grasses. Again, temperatures of 30°, 29°, and even 28° have been observed when no 
frost was seen, but unless frost is looked for on such mornings at the ver}^ time of minimum 
temperature, there is no proof that frost did not occur. When the temperature is below freezing 
for a brief period only, light frost may form for a few minutes just before daybreak, and disappear 
as soon as the temperature rises to the melting point. Even should frost occur during any night 
in summer, the temperature would have risen above the freezing point by sunrise. 



Ill 

-MixiMUM Temperatures at Weather Bureau, La Crosse, Wis., and at Different Locations at 
Mather, Wis., Season of 1907. 



May. 



Day of month. 



8.. 

9. 
10. 
11. 
12. 
13. 
14. 
15. 

le. 

17. 
18. 
19. 
20. 
21. 
22. 
23. 
24., 
25.. 
26.. 
27.. 
28.. 
29.. 
30.. 
31.. 



Readings 

from 

Weather j 

Bureau 

olTice , i 

La Crosse,; 

Wis. I 



Shelter on 

vipland, 

Mather. Wi.s. 



Shelter on 
marsh, over 

moss, 
Mather, Wis. 



Read- 
ings. 



1 : 

2 

3 - -..' 

4 

6 ' 



Means. 



Ditler- 
ence. 



Read- 
ings. 



Differ- 
ence. 



At 5 inches 
above marsh, 

over moss, 

in open, 

Mather, Wis. 



Read- 
ings. 



+ S 
+ 4 

- 2 
-10 



-li 

- 1 

- 3 

- (5 

- 3 
+ 3 

- 



40.9 -3.8 



38.1 



- 8 

-I- S 
+ 4 

_ 2 
-15 
-15 

- 9 
-12 
-18 

- 2 

- 3 

- 8 

- 3 
+ S 
~~ 7 
-10 
-16 
-14 

- 4 



-6.6 



Differ- 
ence. 



35 { 

eo 

45 

36 

34 

32 \ 

32 

28 

la 

21 
44 
44 
40 
44 
45 
27 
27 
30 
36 
45 



36.2 



-10 

+ 4 

+ 4 



- 3 
-18 
-18 
-14 
-15 
-20 

- 2 

- 3 
-10 

- 4 
-I- 6 
-11 
-14 
-SO 
-17 

- 5 



June. 



Readings 

from 

Weather 

Bureau 

office. 

Lacrosse, 

Wis. 



56.2 



Shelter on 

upland. 

Mather,' Wis. 



Shelter on 
marsh, over 

moss, 
Mather, Wis. 



Read- 
ings. 



Differ- 
ence. 



- 5 
-12 

- 2 
-12 

-n 

- 4 
-10 

- 1 

- 5 
-11 
-12 
-U 
-1- 2 

- 6 
_ 2 

- 7 
-10 

- 5 



- o 

- 6 

- 7 
-13 
-11 

- 6 



49. 1 -7. 1 



Read- 
ings. 



Differ- 
ence. 



At 5 inches 
above marsh, 

over moss, 

in open, 

Mather, Wis. 



Read- 
ings. 



45.4 ! -10.8 



Differ- 
ence. 



-17 

-18 
o 

-13 

— n 

-18 

— 5 

-211 

-a 

— 5 

-18 

— 4 
—15 

-Ul 
—20 
-19 

— 5 
— 1,"> 
-12 
—IB 
-18 

-12 
-12 
-10 
-13 
-17 
-19 
-19 



Note.— Columns headed " Difference " have in every case reference to the readings at the La Crosse office as compared with readings at 
the various exposures at Mather. 

Highest and lowest readings are in italics. 
51936°— Bull. T— 10 S 



112 



Table 22. — Minimum Temperatures at Weather Bureau, La Crosse, Wis., and at Different Loj^tioxs at 

Mather, Wis., Season of 1907— Continued. 





July. 






August. 






Day of moil th. 


Readings 

from 
Weather 
Bureau 

office, 
La Crosse, 

Wis. 


Shelter on 

upland, 

Mather, Wis. 


Shelter on 

marsh, over 

moss, 

Mather, Wis. 


.\t 5 inches 
above marsh, 

over moss, 

in open, 

Mather, Wis. 


Readings 

from 

Weather 

Bureau 

office, 

Lacrosse, 

Wis. 


Shelter on 

upland, 

Mather, Wis. 


Shelter on 
marsh, over 

moss, 
Mather, Wis. 


At 5 inches 
above marsh, 

over moss, 

in open, 
Mather, Wis. 




Read- 
ings. 


Differ- 
ence. 


Read- 
ings. 


Differ- 
ence. 


Read- 
ings. 


Differ- 
ence. 


Read- 
ings. 


Differ- 
ence. 


Read- 
ings. 


Differ- 
ence. 


Read- 
ings. 


Differ- 
ence. 


1 


58 
60 
59 
65 
70 
64 
61 
65 
64 
60 
62 
59 
63 
63 
66 
62 
61 
60 
67 
64 
66 
66 
60 
69 
65 
58 
57 
63 
61 
57 
62 


59 
S8 
48 
51 
60 
58 
SI 
59 
61 
50 
60 
51 
54 
62 
6S 
51 
57 
50 
56 
61 
64 
64 
53 
64 
63 
49 
45 
59 
57 
53 
58 


-1- 1 
-12 
-11 

-H 
-10 

- 6 
-10 

- 6 

- 3 
-10 

- 2 

- 8 

- 9 

- 1 
+ S 
-11 

- 4 
-10 
-11 

- 3 

- 2 

- 2 

- 7 

- 5 
-12 

- 9 
-12 

- 4 

- 4 

- 4 

- 4 


55 

3« 
41 
47 
61 
55 
46 
50 
54 
45 
60 
44 
47 
61 
68 
49 
48 
47 
53 
53 
62 
60 
54 
61 
53 
46 
45 
57 
51 
46 
53 


° 

- 3 
-18 
-18 
-18 

- 9 

- 9 
-15 
-15 
-10 
-15 

- 2 
-15 
-16 

- 2 
4- S 
-13 
-13 
-13 
-14 
-11 

- 4 

- 6 

- 6 

- 8 
-12 
-12 
-12 

- 6 
-10 
—11 

- 9 


52 
19 
38 
45 
59 
53 
43 
47 
51 
42 
60 
42 
44 
56 


- 6 
-11 
-SI 
-20 
-11 
-11 
-18 
-18 
-13 
-18 

- 2 
-17 
-19 

- 7 


53 
52 
51 
60 
63 
64 
61 
63 
62 
S9 
63 
58 
60 
62 
64 
64 
58 
66 
58 
50 
52 
51 
61 
57 
52 
59 
60 
60 
61 
66 
89 


55 
46 
48 
89 
59 
54 
57 
55 
54 
59 
74 
53 
50 
53 
56 
61 
52 
57 
65 
43 
47 
43 
54 
64 
48 
51 
56 
58 
51 
64 
58 


+ 2 

- 6 

- 3 
-11 

- 4 
-10 

- 4 

- 8 

- 8 
-10 
+ 11 

- 5 
-10 

- 9 

- 8 

- 3 

- 6 

- 9 
-1- 7 

- 7 

- 5 

- 8 

- 7 

- 3 

- 4 

- 8 

- 4 

- 2 
-10 

- 2 
-II 


52 
43 
43 
36 
59 
48 
51 
53 
52 
57 
72 
43 
46 
49 
54 
59 
47 
51 
65 
39 
40 
38 
51 
45 
38 
46 
55 
54 
48 
64 
55 


- 1 

- 9 

- 8 
-14 

- 4 
-16 
-10 
-10 
-10 
-12 
-1- 9 
-15 
-14 
-13 
-10 

- 5 
-11 
-15 
+ 7 
-11 
-12 
-13 
-10 
-12 
-14 
-13 

- 5 

- 6 
-13 

- 2 
-14 


47 
39 
40 
34 
58 
46 
' 48 
51 
49 
55 
70 
40 
42 
46 
50 
58 
43 
48 
65 
34 
36 
34 
47 
41 
S3 
42 
56 
SO 


- 6 


2 


-13 


3 


-11 


4 


-16 


6 


- 5 


6 


-18 


7 


-13 


8 


-12 


9 


-13 


10 


-14 


11 


+ 7 


12 


-18 


13 


-18 


14 


-16 


15 


es + g 


-14 


16 


46 
45 
44 


-16 
-16 
-16 


- 6 


17 


-15 


18 .. 


-18 


19 


52 -15 

50 -14 


+ 7 


20 


-16 


21 


60 
57 
50 
59 
49 
42 
41 
55 
48 
45 
48 


- 6 

- 9 
-10 
-10 
-16 
-16 
-16 

- 8 
-13 
-12 
-14 


-16 


22 


-17 


23 


-14 


24 


-16 


25 


-19 


26 


-17 


27 


- 4 


28 


-10 


29 


44 1 -17 


30 


62 1 - 4 


31 


52 j -17 






Means 


62.2 


55.6 


-6.6 


51.7 


-10.5 


49.0 


-13.2 


59.3 


54.0 


-5.3 


50.1 


-9.2 


47.1 ! -12.2 









Note.— Columns headed " Difference" have in every case reference to the readings at the La Crosse oflBce as compared with readings at 
the various exposures at Mather. 

Highest and lowest readings are in italics. 



113 

Table 22.— Minimum Temperatures at Weather Bureau, La Crosse, Wis., and at Different Locations at 

Mather, Wis., Season of 1907 — Continued. 



Day of month 



September. 



October. 



Readings 

from 
Weather 
Bureau 

olEce, 
Lacrosse, 

Wis. 



Shelter on 

upland, 

Mather, Wis. 



Read- 
ings. 



Differ- 
ence. 



Shelter on 

marsh, over 

niosSj 

Mather, Wis. 



Read- 
ings. 



Differ- 
ence. 



At 5 inches 
above marsh, 

over moss, 

in open, 

Mather, Wis. 



Read- 
ings. 



Differ- 
ence. 



Readings 

from 

Weather 

Bureau 

office. 

La Crosse, 

Wis. 



Shelter on 

upland, 

Mather, Wis. 



Read- 
ings. 



Differ- 
ence. 



Shelter on 
marsh, over 

moss, 
Mather, Wis. 



Read- 
ings. 



Differ- 
ence. 



At 5 inches 
above marsh, 

over moss, 

in open, 

Mather, Wis. 



Read- 
ings. 



Differ- 
ence. 



3. 

4. 
5. 
6. 
7. 
8. 
9. 
10. 
11. 
12. 
13. 
14. 
15. 
10. 
17. 
18.. 
19., 
20.. 
21.. 
22.. 
23.. 
24.. 
25.. 
26.. 
27.. 
2S.. 
29.. 
30.. 
31.- 



Means- 



50.7 



70 
53 
50 
52 
44 
41 
54 
56 
40 
38 
45 
48 
50 
62 
63 
67 
53 
58 
61 
60 
38 
31 
45 
43 
S8 
34 
34 
37 
29 
18 



47.1 



-I- 8 

- 2 

- 6 

- 1 

- 6 

- 9 

- 5 
+ 9 

- 5 

- 8 

- 4 

- 4 
-10 

- 2 

- 3 
-I- 4 

- 8 
'-4 

- 5 
+10 

- 4 

- 7 

- 2 
-I- 3 

- 5 

-;/ 



-3.6 



44.3 



+ 3 



- 9 
-12 

- 3 
-I- 9 

- 9 
-10 

- 7 
-12 
-16 

- 5 

- 8 
-I- 3 
-13 

- 4 

- 5 
+ 9 

- 7 

- 9 

- 4 
-I- 3 

- 8 
-16 
-10 

- 4 
-U 
-11 



- 1 

-13 
-16 

- 8 
-14 
-17 

- 4 
-I- 9 
-15 
-16 
-12 
-15 
-SO 

- 7 
-12 
+ 1 
-17 



-I- 7 
-12 
-15 
-10 

-13 

-eo 

-15 
- 8 
-15 
-17 



-6.4 



38.2 



33 
52 
46 
41 
41 
44 
50 
23 
40 
35 
35 
29 
25 
22 
44 
36 
39 
24 
27 
28 
19 
40 
30 
29 
28 
19 
34 
17 
32 
37 
37 



33.4 



-16 

- 3 

- 7 

- 3 

- 4 
-II 
+ 10 

- 9 


- 5 

- 4 

- 4 


-12 

- 3 



- 5 

- 4 

- 9 

- 2 

- 4 
-11 

- 2 
-10 
-I- 9 

- 5 
-10 

- 4 
+ 2 



-17 

- 6 
-13 
-12 
-12 
-16 
-I- 1 
-11 

- 1 
-11 

- 7 

- 5 

- 4 
-14 

- 4 
-10 
-14 

- 9 

- 9 

- 5 
-10 

- 7 

- 7 
-17 

- 6 
-11 
-I- 7 

- 6 
-13 

- 5 

- 1 



-4.1 



29.9 



-8.3 



-10 
-17 
-17 
-IS 
-21 

- 3 
-16 

- 7 
-15 
-13 
-10 

- 9 
-18 

- 8 
-15 
-17 
-14 
-14 
-10 
-15 
-11 
-12 
-12 
-13 
-17 
+ 4 

-12 
-16 

- 6 

- 5 



-12.9 



Highest and lowest readings are in italics. 

Table 22a. — Monthly and Seasonal Means of Minimum Temperatures at Weather Bureau, La Crosse, Wis., 
AND AT Different Locations at Mather, Wis., together with Differences between the Readings, 1907. 



Maya 

June 

July 

-Vugust 

September. . 
October 

Means 



, Shelter on upland, 
Readings, Mather, Wis. 

La Crosse, 
Wis. 



44.7 
.56.2 
62,2 
59.3 
60.7 
38.2 



51.9 



Readings. Difference. 



40.9 
49.1 
55.6 
54,0 
47.1 
33.4 



46.7 



-3.8 
-7.1 
-6.6 
-5.3 
-3,6 
-4,8 



-5.2 



Shelter on marsh, over 
moss, Mather, Wis. 



Readings. Difference. 



38.1 
45.4 
51,7 
50.1 
44.3 
29,9 



43.2 



-6,6 
-10.8 
-10,5 
-9.2 
-6.4 
-8,3 



8.7 



At 5 inches above 
marsh, over moss, in 
open. 



Readings. Difference. 



36.2 
42.3 
49.0 
47.1 
40,4 
25.3 



40.0 



- 8.5 
-13.9 
-13.2 
-12.2 
-10,3 
-12.9 



-11,9 



o Means for twenty days. 

Note.— Columns headed "Difference" have in every case reference lo the readings at the La Crosse office as compared with readings at 
the various exposures at Mather. 



114 

Temperature conditions in the bogs during the seasons of 1908 and 1909. — The principa4features 
of the season of 190S in the Wisconsin bogs were as follows: Frost occurred on June 11 and 15 at 
both Cranmoor and Mather, the exposed minimums in the bog at the latter station being 29°, and 
28.9°, respectively; frost was again noted at both stations on August 20, 23, and 24; and again 
in September on the 2d and the 8d, the rest of the month being warm until the 28th when kill- 
ing frost occurred; also on tlie 29th and 30th. There was ample water supply in the Wis- 
consin bogs for reflowing, and no ilamage, as a consequence, occurred to the crops from these 
frosts. 

In 1909, frost occurred at Mather, June 15 ami 18, but no frost was reported at Cranmoor 
on any date in June. Frost was again reported at Mather on July 19, when the lowest exposed 
minimum was 29°. On that date the lowest temperature at Cranmoor was 32.8°, but no frost 
was observed. On August 30, frost was observed at Mather, but none at Cranmoor, the minimum 
at Mather registering 23°. The temperature was unusually low in the bogs during September, 
in strong contrast to the September of 1908, frost being reported on 11 dates at both Mather 
and Cranmoor. On these days the exposed minimums over moss at Mather were as follows : 



September 25 14 

September 26 13 

September 27 12 

September 28 26 

September 30 22 



September 1 ■. IS 

September 2 16 

September 6 22 

September 16 24 

September 23 24 

September 24 22 

These conditions were most extraordinary, and following, as they did, a season of compara- 
tive drouth, the growers were unable to properly reflow their marshes. In fact the larger portion 
of the Wisconsin crop was destroyed by the frosts of September 1 and 2, 1909, not more than 
25 per cent of the entire crop being eventually saved. 

The conditions as shown by the weather map indicated ])lainly the coming of the frosts 
during the year 1909, and ample warnings were issued from the forecast center at Chicago. It 
is unfortunate that water supply was not available for reflowing, as in previous j^ears. The 
season of 1909 in the moorland sections was the driest in about a dozen years, while in the few 
years immediately preceding, there was complaint of too nuich rainfall lather than of too little. 

Temperature of the water in fJie reservoir. — Much has been said already about the low tem- 
perature prevailing over damp ground, and it has been shown that over a saturated soil the 
minimum temperature, especially on clear, cool nights is low. It ma}' therefore seem strange 
that additional water is used in order to ward ofT frost. A reser^'oir usuallj- has about three 
times the acreage of the bog that it is intended to flow or reflow. The time required to flow a 
marsh depends upon the head of water at the main gate of the reservoir, afid upon the depth 
of the water already in the ditches. If the ditches are nearly empt}-, much time is requireil, 
but the Wisconsin growers usually have water in their ditches up to within about a foot of the 
surface of the marsh. Through cai)illarity this water rises through the peat, ami if the water 
is within 6 inches of the top of the ditches the marsh is very wet. By pressing down upon 
the soil along the edge of the ditches, even though the water therein is considerabl}' below the 
surface of the marsh, the water is squeezed out as from a sponge. During a dry, warm season, 
growers are accustomed to let the water remain low in the ditches, in order to save their supply, 
but as cold weather approaches it is the custom to turn on additional water from the reser- 
voir. It is often possible to reflow an entire marsh in from two to four hours. The water in 
the reservoir is usually comparatively warm, and although it loses heat as it passes through 
the ditches on a cool night, light frost is sometimes avoided by merely increasing the depth of 
the water in the ditches. At other times, however, the water is raised just to the surface of 
the marsh, and only when a severe frost is expected are the vines and berries completeh' covered 
with water. The water turned onto the marsh on these occasions in anticipation of frost usually 



115 

has a high temperature as compared with the water that is found from day to day in the peat 
soil of the bog. This latter partakes of the temperature of the soil itself, and is one of the 
important factors in preventing the heating of that very soil in the daytime, and consequently 
one of the direct causes of the low minimum air temperatures at night. If the water is low 
in the reservoir, as happens during a drought, and during a cool period its temperature is reduced, 
nothing can be gained by flowing unless there is sufficient supply to completely cover the bog. 
To bring this cold water just to the surface would be to reduce the temperature of the air still 
further by evaporation. Reference has already been made to the drouth in the Wisconsin 
bogs in the summer of 1909. Few growers had sufficient water supply to reflow in anticipation 
of the severe frosts of September 1 and 2 of that year, and it has been said that the growers 
who did not attempt to reflow suffered less injury than those who used their limited supply 
of water, chilled as it must have been. 

While, as has been stated before, in order to be effective, the acreage of the reservoir should 
be three times that of the cranberry marsh, the reservoir of the Fitch marsh at Berlin was 
hardly half the size. There are other marshes in Berlin that have no protection in the shape 
of reservoirs. The Sackett. marsh depends upon the Fox River for its water supplj^, the water 
being pumped from the river whenever there is need of flowing or reflowing. 

A Richard soil thermograph placed in the reservoir at the Appleton marsh, with its bulb 
about 12 mches below the surface, has furnished an interesting sei'ies of readings of water tem- 
perature for the season of 1907. (Fig. 14.) The temperature of the water responded to the 
varying changes in the temperature of the air. There was an irregidar increase through June 
and July to the middle of August, the highest maxunum occurring on August 7, 79°, with 
the exception of a maxunum of 81° which occurred on June 17 and 24, during and following 
a protracted period of high temperature. The highest minimum, 73°, occurred on June 22 
and August 11. The highest and the lowest temperatures each month were respectively as 
follows: May, 67° and 42°; June, 81° and 53°; July, 77° and 66°; August 79° and 58°; Sep- 
tember, 70° and 46°; October, 60° and 35°. The absolute range for the season was therefore 
46°. The following are the mean daily maximum and minmium temperatures each month: 
May, 58° and 49°; June, 70° and 63°; July, 74° and 69°; August, 70° and 64°; September, 
61° and 55°; October, 49° and 42°. Throughout the season, the lowest temperature of the 
day usually occurred at about 5 a. m. and 6 a. m. The maximum occurred in May at 4 p. m., 
and as the season advanced it occurred later and later each day until midsummer, after which 
it gradually occurred earliei' in the afternoon, so that in October the time of maximum was 
2 p. m. The greatest daily range in the temperature of the water was 16° on June 1, and there 
were a number of days when the temperature varied only 2° or 3°, during cloudy weather. 
The lowest temperature in October, 35°, occurred on the night of the 27th-28th. Figures 26 
and 27, previously referred to, show the relation existing between the temperature of the water 
in the reservoir and the temperature of the air and of the soil at Mather, Wis., for two selected 
weeks in 1906. 

Observations were not made regularlj' of the temperature of the water in the ditches, but 
there is no doubt that on clear, cool nights it was much lower than that in the resei-voir, as the 
latter had considerably less volume and lay in the midst of the cold bog. Observations made 
at Berlin on October 1, 1906, showed a temperature of 53° m the reservoir, and temperatures 
of 37° and 39° in two small ditches. The ditches at Berlin where these observations were 
taken were shallow, the water being scarcely more thai> a foot in depth. At Mather, on the 
other hand, the ditches were 3 feet in depth, and they were consequently able to carry a con- 
siderable volume of water. 

While the water turned on from the reservoir into the ditches gradually loses heat, it, in 
turn, communicates heat to the marsh even before the surface of the marsh is covered. The 
thermograph sheet shows several instances when, after the water had been turned on, not only 
the fall in temperature over the bog was ari-ested, but a rise actually occurred for a brief periotl, 
although this was followed again by a fall. The thermograph sheet, at Station 3, in the open 



116 



for June 5-6, 1907, shows this graphically. (Fig. 30.) At about 10 p. m. the temperature 
had fallen to 37°; during the next two hours an irregular curve was described. At midnight 
the temperature had risen to 42°, after which it gradually fell. On the same night, the ther- 
mograph trace of the instrument at Station 5, on the bog, shows that from 10 p. m. until nearl}^ 
midnight the fall in temperature was retarded somewhat. (Fig. 30.) The water in reflo wing 
was colder upon reaching Station 5, as it was farther away from the reservoir than Station 3 ; 
moreover, on the night of June .5, the water was not so high in the section around Station 5 
as around Station 3, on account of the slight difference in elevation of the two stations. The 
lowest temperature at Station 3 was 33°, while at Station 5 it was 32°. At Station 2, over 
moss and outside the cranberry marsh where flooding was not practiced, the minimum tem- 
perature was 28°. The temperatures at Stations 2 and 5 as a rule differed but little, as stated 



5th 
noon 



mdi 



JUNE, 1907. 
6th 5th 

noon noon 



mdi noon 




Fig. 30. 
Station 3 Station 5 

Thermograph trace in "open " over bog from noon. .June 5, 1907, to noon, June 6, 1907, showing effect of flow- 
ing of marsh on temperature of air. Stations 3 and .5, Mather, Wis. 

before, the average difference between the exposed minimums at the 5-inch height for the 
entire season of 1907 being but 0.1°. It is therefore probable that reflowing the marsh on this 
night was responsible for the difference in temperature of 4° between Stations 2 and 5. 

CONCLUSION. 

Advantages gained from sanding, draining, and cultivating. — It is obvious from a study of 
the obser\^ations presented in the foregoing tables that sanding, draining and cultivating seiwe 
to decidedly modify low night air temperatures; and it is strange, at first thought, that Wis- 
consin growers do not sand their marshes. Many of them, however, object to the use of sand 
on the ground that the natural peat soil produces cranberries of better quality. Again, as 
previously stated, gravelly sand, such as is used on Cape Cod, is not available in the moorland 
region of Wisconsin, and ordinary fine sand packs too closely and permits a rank growth of 
vegetation. The Wisconsin grower states that he can secure better returns financially by 
using his money in extending his marsh rather than in sanding it, because there are vast 
areas in Wisconsin available for cranberry culture as compared with the restricted region of 
Cape Cod; and that if the vines are planted in sand, the cost of preparing the bog for planting 



117 

is doubled, without doubling the returns as a result; but this statement is not accepted by 
Professor Whitson and his assistants connected with the experiment station at Cranmoor. 
As a matter of fact, the average .yield per acre in Cape Cod is 40 barrels; in New Jersey, 30 
barrels; and in Wisconsin, only 20 barrels. There are even authentic reports of 200 barrels 
per acre raised on Cape Cod under most favorable circumstances. It is not denied, however, 
that sanding is valuable in warding of frost, and the fact that reflowing is seldom required at 
the experiment station where intensive farming is practiced is, of itself, of the greatest impor- 
tance. Sanding is obviously needed far more in Wisconsin than in Massachusetts, because 
the temperature averages much lower in Wisconsin, as has been shown in the introduction of 
this bulletin. If sanding had been practiced generally in Wisconsin, much of the crop that 
was destroyed by the frosts in September, 1909, through lack of water for reflowing, would 
have been saved. The estimated damage, as a result of the frosts of September 1 and 2, 1909, 
alone, to the entire Wisconsin crop was 50 per cent, while the loss at the Cranmoor Experi- 
ment'station was onlv 2 per cent. Moreover, only about 2.5 per cent of the crop was eventually 
saved because of the numerous severe frosts later in the month, to which reference has already 

been made. , rn 

The sanding is usually done during the winter, when the flood covers the marsh, ihe 
sand is spread over the ice" and it gradually smks to the surface of the bog in the spring as the 
ice melts." Cape Cod growers generally sand every few j-ears, adding a layer of about half an 
inch in thickness, but in Wisconsin no regular custom has been followed. While the greater 
portion of the Ap'pleton marsh at Mather had been sanded to a depth of about 2 inches in 1898, 
no further sanding was done until the winter of 1905-6, when a portion of the marsh previously 
sanded was covered with another layer. Weeding or cultivating has been practiced to a con- 
siderable extent, but the growth of vegetation is so rank in many of the bogs that much work 
is required in order to make any showing. The drainage is steadily being improved, the ditches 
have been placed closer together and are usually kept clean so as to assist in draming as well 
as in rapid reflowing. 

A study of ihe general and local conditions necessary for frost in the marshes.— The. natural 
conclusion from the data presented is that the study of local conditions in the marshes is of 
much importance. It is apparent that the temperature varies greatly in adjoining bogs and 
even in different portions of the same bog. During a frosty night damage may result in one 
portion of a bog and not in another, but serious frosts are usually general and not local. A 
grower may wish to conserve the water supply if the season is dry and the water low, because 
if he makes too liberal use of it, means for reflowing may not be at hand later when great danger 
threatens. In view of the fact that reflowing should not be resorted to any oftener than is 
absolutely necessary, the forecaster and the grower have between them a problem to solve 
that is sometimes very difficult. When low temperature threatens it must be first determined 
whether the night is to be clear, the barometer high, and the wind light. Of greatest nnpor- 
tance is the clearness of the atmosphere, as there will be no decided fall in temperature durmg 
any night unless the clouds clear away; even passing clouds over a marsh often raise the tem- 
perature several degrees. But local conditions seldom determine the condition of the sky. 
The reasons for cloudiness must be found in the movement of the areas of high and low 
pressure; and these reasons are not always apparent on the face of the weather map. The 
work of forecasting frost for the cranberry marshes is important and requires constant vigilance. 
True it is that damaging frosts seldom occur in midsummer. The frost of August 7-8, 1904, 
was abnormal— in fact, a phenomenal condition. The forecaster should know that such a low 
temperature is not likely to happen in every July or August, because it is far from being the 
fact, and it can only occur under circumstances on every side favoring its development. It is 
therefore a well-marked condition— one that would attract the attention of the forecaster almost 
instantly as he scans the weather map. Ordinarily, areas of high barometer do not bring frosts to 
the cranberry marshes of ^Yi.sconsin in the midsummer months, even though they are of considerable 
magnitude, have comparatively low temperature, an d move across the northern tier of states. 

<• In Massachusetts the sanding is now done mostly in the autumn, before the winter flow has been turned on. 



118 

The temperature of the soil is usually too high during the warm season to permit the 
formation of frost, and it is quite impossible for it to occur during these months followi^ a day 
of sunshine. On the other hand, frost occurs easih' in the moorlands on clear nights during 
the spring, early summer, and autumn when the soil is cold. As stated before, the conditions 
such as obtained during June 11, 12, and 13; 1906, would not be sufficient to cause frost later 
in the summer after the ground had become warm. In determining whether frost warnings 
should be issued, not only the weather maps must be studied carefully, but also the tempera- 
ture conditions in the bogs produced by recent hot or cold spells. The temperature of the 
soil is an important factor at any period of the growing season, and the reading of the maximimi 
thermometer is of mucli value, indicating, as it does, in a measure, the amount of heat conveyed 
to the soil during the daytime. Should the maximum temperature in the shelter he helow 70° on 
any day, and he followed at night hy clear sicy and light wind, harometer above normal and rising, 
there is strong prohahility that frost will follow in the hogs, especially if the pressure reaches a height 
of SO. 20 inches or more and the center of the HIGH passes over Wisconsin or the Lake Superior region . 
The theory that frost does not follow rain has no foundation. In fact, a day of light rain 
accompanied by a fresh wind which facilitates evaporation at the surface of the soil is often 
followed by a frosty night, as evidenced b\' numerous instances in 1907. (See Table 22.) 

Should it be expected that the minimum temperature at La Crosse or St. Paul will fall 
below 50°, ordinarily there is danger of damage in the cianberrv marshes on any clear night. 
Severe frosts have occurred in the bogs when the temperature at La Crosse was no lower than 
48°, as on August 8, 1904, previously referred to. The temperature ''in the open" at the 
coldest place in the bog must fall below 29° in order that serious damage may occur. Probably 
a temperature for several hours "in the open" as low as 29° would be serious, but there are 
many instances of minimum temperatures of 29°, and even of 28°, when no frost or resulting 
damage was apparent. 

While frost may occur with a pressure not above normal during tlic spring, early summer, 
and autumn, this is not possible during the months of July, August, or early September. The 
barometer over the moorlands during the warm months must attain a height of at least .30.20 
inches, so as to permit the cold air to gradually settle over the bog. On July 2, 1907, when 
the temperature fell to 29° at Mather with the pressure of 30.10 inches, no frost was observed, 
but it is probable that if the pressure were as high as 30.20 inches, a frost would have occurred. 
The higher the pressure the heavier the air, and the lighter the wind tlie more easily the cold 
air settles toward the groimd. 

As stated previously, it is important to determine from the weather map whether the 
weather will be clear over the moorlands because, regardless of how cold it is in tlie Northwest 
and how threatening tlie conditions, tliere can be no damage done during the growing season 
if the weather is cloudv at night; but severe frost mav occur earlv in ilav before the ^rro^^^n^ 
season, and in October after the berries have been picked, on cloudy and windy nights, but no 
damage can then result in the marshes. A perfect condition for frost in the moorlands exists when 
a liigh-pressure area from the Northwest moves eastward with the center over Lake Superior, 
sending cool north winds thence over Wisconsin, or when the HIGH settles directly over the 
moorlands, following a da}', or preferably two, of cloudiness, with some rain and wind, provided 
the clouds clear away and the wind subsides in the evening as the temperature begins to fall." 
^Miile the study of local conditions is of value — temperature and its rate of fall, wind direction 
and velocity, humidity and pressure — these conditions may not. during inisettled conditions, 
assist materially in determining whether the weather will clear ami frost occur before the 
following morning. A strong, steady rise in pressure is the best local indication for clearing 
weather, and without this the weather \dll probably remain cloudy. AVliile a high jn-essure 
area moving eastward and southeastward over the Lake region is usually accompanied by clear, 
cool weather, occasionally the movements of such areas are abnormal and cloudiness persists in the 
front of the HIGH. A riMiiarkable instance of persistent cloudiness was noted from September 

o When a HIGH moves rapidly across Wisconsin, tlie barometer begins to fall and the wind lo rise immediately after the passage of the 
crest. Under .such conditions. :i falling temperature up to midnieht is followed by rising temperature during the balance of the night . 



I 



119 

2 to 5, 1905. On three successive days the pressure was high in the Northwest, reaching 30.44 
inches at Prince Albert, and accompanied b}' freezing temperatures. This area moved slowh' 
southeastward, gradually losing force, but nevertheless maintaining low temperatures. On the 
morning of September 4 the pressure was highest over Manitoba, and frost was general throughout 
the Dakotas. The weather, however, although cold in the moorlands, never cleared during 
the entire period. Temperatures were as low as 37° on two successive nights, but by reason 
of the continued cloudiness frost did not occur in the bogs. A study of the local conditions, 
aside from the pressure, would not have enabled a person to determine whether it would clear 
on either of these nights. The cloudy weather covered a considerable area, in fact, several 
states, and the reason for this condition could not be found in the moorland sections of Wisconsin. 
Similar instances have been noted in other Septembers. Wlien cloudy weather prevails over a 
large area in front of a HIGH, it may ordinarily be expected to continue, unless there is a steady 
increase in pressure between the LOW and the HIGH. In case of doubt, special observations 
should be called for by the forecaster in the middle of the afternoon from the cranberry marshes 
and a few stations in the Northwest, with special reference to the maximum temperature in 
the bogs and the probability of clear weather for the ensuing night. It might be well to have 
an observation of soil temperature included in the reports from the cranberry marsh stations 
each morning in addition to the data usually telegraphed. 

The maps of August 7 and 8, 1904 (Figs. 4, 5), have been included in this bulletin, illus- 
trating a perfect contlition for the occurrence of frost. The cloudy weather during the 6th and 7th 
had prevented the usual warming of the soil, and the breezy weather of the 7th, through evapora- 
tion of the moisture near .the surface, evidently caused the soil to become colder. The maximum 
temperature in the shelter on August 6 was 76° at Mather and Cranmoor, and on August 7 it 
was 65° at Mather and 67° at Cranmoor. We have already showii what a great effect the 
temperature of the soil has upon the temperature of the air near the surface during any night, 
and that in marshes the places covered with dense vegetation, with thick matting of moss or 
thick growth of vines or ferns, are the ones of lowest temperature, especialh' if the soil has 
not been sanded and the drainage is poor. Wlien the soil is largely protected from the sun's 
heat by vegetation and the initial temperature at the surface is low in the evening, compara- 
tivel}' low minimum temperatures must result if the night be clear. The situation is even more 
pronounced if the previous day has been cloudy, because, as a consequence, the storing of heat 
in the soil has been interrupted and the point of critical temi)erature may therefore be reached 
more readily. Tlie relation between the temperxiture of the soil and the occurrence of frost is noticeahle 
in that it is practically impossible for frost to occur in the bogs on the first cool night following a warm 
spell, but it is lUtehj, if conditions are farorahle, on the second night after the soil has become cold. 
Growers claim, and with reason, that frost almost invariably occurs on the sec(jnd night of a 
oold spell, and even if it does occur on the first night the frost on the second night is likely to 
be more severe. 

Frost remains in the soil of an unflooded bog until cnmparatively late in the season, anfl 
there have been found instances of frost in the soil in nuxrshes as late as July 4. I'sually, 
however, when the winter flow is taken off in the spring the soil is free from frost. The temper- 
ature of the soil tends to gradually increase until after midsummer, and then gradually decrease 
again. The soil being cold in the spring and early summer, and again in the fall, frost is more 
likely to occur then, regardless of the accompanying conditions of atmospheric temperature and 
pressure. That is, the ground being cold, frost will occur in the marshes in May and early in June 
under the'injluence of areas of high pressure and accompanying low temperature that would be far 
from sufficient to cause frost during the midsummer months, when heat has been stored up in the soil. 
The length oftlte nights is also very important in estimating the probahiJity oftJie occurrence of frost, 
especially during the months of September and October, as the nights steadily grow longer and afford 
greater opportunity for radiation, without compensating insolation. 

The forecaster must have in mind the lowest temperature that may occur in the less- 
favored sections of the marsh, as it is evident that a wide range in temperature will be found 
in practically all marshes. Even with the knowledge that the lowest temperature "in the 



120 



open" will fall below the freezing point, it is not certain that there will be any damage. In 
fact, as has been stated before, the result of the investigation indicates that the temperature 
"in the open" must fall 2° to 4° below the freezing point in order to cause any serious damage, 
But the forecaster need not be the judge of what damage may ensue. It is for him to issue 
warnings, stating in his forecast the probabihty of light, heavy, or killing frost, and, if possible, 
how long the cool condition is hkely to last; because such information will often assist the 
cranberry grower in conserving his water supply. It is very important to know the hour in 
the evening that the frost is hkely to set in, because if it begins to form before midnight the 
damage to unprotected raarshes is certain to be serious, as the period of freezing in that event 
will continue through several hours till daybreak. When, however, the frost does not begin 
to form until nearly dawn there is little probabdity of damage. For traces of the curves at 
Berhn during the nights of September 13-14 and 27-28, 1906, see Figure 31, showing first 
in one instance a fall to freezing for only a brief period and in the other the temperature 
remaining at a low point for several hours. 



SEPTEMBER 

noon mat 



noon 



SEPTEMBER 

noon mat noon 




Fig. 31.— Berlin, Wis., ;906. 
Temperature curves in the vines on the marsh. Examples of two days — first, when minimum temperature 
touched freezing point for a few minutes — second, when the temperature remained at freezing for several hours. 
Irregularity of curves in both cases due to wind or passing clouds. 

There is an opportunity for tlie forecaster to give great assistance to the cranberry grower 
and to place in the hands of the latter all the information that may be available. If possible, 
it is advisable to send advice twenty-four hours or more in advance at times when the growers 
have the water supply low in the ditches, as is customary in the summer time, in order to enable 
them to raise the water, thus permitting easy flooding on the ensuing day. With this assistance 
the most improved marsh can then be flooded in a brief period. Man}' growers state that they 
want advice even wlien /ros< is possible, as well as prohahle, so that they may never be found entirely 
unprepared. If the water is allowed to get very low in the ditches, it may take twelve hours 
or more to flood, as the dry, spongy bog absorbs an immense amount of water. The grower, 
having been properly informed, can act accordingly, taking into consideration the probable 
conditions, the amount of Ins available water supply, and the possible damage, should he not 
reflow his marsh. When the water is warm during the summer season, and a light frost is 
expected, danger can usually l)e averted by raising the water no higher than the surface of 



121 

the marsh; yet such flooding affords but httle protection should a severe freeze occur. The 
grower is well acquainted Math the conditions of the vines and the fruit, and knows from 
experience when they are most liable to damage. He understands that at certain times during 
the season the marsh is practicall}^ immune to damage. For instance, after the winter flow 
is taken off in the spring and before the terminal buds have swollen and begun to burst there 
is little danger of damage, but later the liabihty is very great. The winter flow is held on 
some marshes later than others, but when it is dra^\^l off after May 15 the buds usualh^ begin 
to swell five to ten days later. After the upright starts out from the terminal bud it is very 
tender, and there is more danger to it than to the fruit bud, as it wiU freeze more easily. The 
fruit blossoms usually appear at Mather about June 10 and the vines are in full bloom about 
July 1. The setting of the fruit begins with the falling of the first blossoms and continues 
until the vines are out of blossom. The new terminal bud is generally formed by August 
10, and often before that date. During 1906 there were many terminal buds fuUv formed 
by August 5. Until the terminal bud is well formed and protected a frost may destroy it, 
and thus ruin the prospects of a crop for the ensuing j^ear, aside from the damage to the crop 
of the current year. The terminal bud, however, is free from damage by frost usually after 
September 1. The fruit itself will freeze most easily just after setting, on account of the large 
amount of water it contains, and the riper the berry becomes the more hardy it is, so that when 
it is fully matured it can not he damaged except by a severe frost. Information of this character 
is of importance to the forecaster, simply because it indicates that the frost ■warnings have 
more value at one time of the year than another; that a frost in July or early in August, for 
instance, may wipe out not onh' the crop of the current year but even the prospects for a crop a 
year later. As an actual result of the freeze of August 8, 1904, the crop of that year in the 
Wisconsin River Valley was reduced about 40 per cent and that of 1905 about 25 per cent. 

It is possible for the forecaster to acquire a high degree of accuracy in special work of 
this character. He should never fail to issue warnings previous to serious frosts, and he seldom 
should make the mistake of issuing warnings for frosts that do not occur, but he should realize 
that it is his duty to save the crop. It is not enough for him to issue warnings in advance of 
ten frosts of wliich the growers take advantage in protecting their marshes, and j^et fail to send 
a warning in advance of the eleventh frost, which results in great injury. He should realize that he 
must carry oti this worTc to a successful conclusion from the beginning to the end of the season, or, 
in other words, that he must "save the crop." He may sometimes be excused for issuing warnings 
that are not verified, especially if there is ample water supply for protection ; but he %vill never 
be excused for failure to issue warnings in advance of serious damage. 

o 



LE N 'I 



W. B. No. 443. Issued Dec. 31, 1910. 

U. S. DEPARTMENT OF AGRICULTURE, 

WEATHER BUREAU. 
BULLETIN T. 



FROST AND TEMPERATURE CONDITIONS 
IN THE CRANBERRY MARSHES 

OF WISCONSIN. 



Prepared under the direction of WILLIS L. MOORE, Chief of Weather Bureau, 

By 
HENRY J. COX, Professor of Meteorology. 




WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 
1910. 









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